Extracted UsbDeviceHandle as interface.

BUG=367094

Review URL: https://codereview.chromium.org/278633003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269803 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 251 insertions, 173 deletions

diff --git a/components/usb_service.gypi b/components/usb_service.gypi
index 5f58d61..2e98e5e 100644
--- a/components/usb_service.gypi
+++ b/components/usb_service.gypi
@@ -25,7 +25,8 @@
       'usb_service/usb_device_impl.cc',
       'usb_service/usb_device_impl.h',
       'usb_service/usb_device.h',
-      'usb_service/usb_device_handle.cc',
+      'usb_service/usb_device_handle_impl.cc',
+      'usb_service/usb_device_handle_impl.h',
       'usb_service/usb_device_handle.h',
       'usb_service/usb_interface.h',
       'usb_service/usb_interface_impl.cc',
diff --git a/components/usb_service/usb_device_handle.h b/components/usb_service/usb_device_handle.h
index 2b03a8a..605e05e 100644
--- a/components/usb_service/usb_device_handle.h
+++ b/components/usb_service/usb_device_handle.h
@@ -16,24 +16,10 @@
 #include "components/usb_service/usb_service_export.h"
 #include "net/base/io_buffer.h"
 
-struct libusb_device_handle;
-struct libusb_iso_packet_descriptor;
-struct libusb_transfer;
-
-namespace base {
-class MessageLoopProxy;
-}
-
 namespace usb_service {
 
-class UsbContext;
-class UsbConfigDescriptor;
 class UsbDevice;
 
-typedef libusb_device_handle* PlatformUsbDeviceHandle;
-typedef libusb_iso_packet_descriptor* PlatformUsbIsoPacketDescriptor;
-typedef libusb_transfer* PlatformUsbTransferHandle;
-
 enum UsbTransferStatus {
   USB_TRANSFER_COMPLETED = 0,
   USB_TRANSFER_ERROR,
@@ -56,24 +42,23 @@ class USB_SERVICE_EXPORT UsbDeviceHandle
   enum TransferRequestType { STANDARD, CLASS, VENDOR, RESERVED };
   enum TransferRecipient { DEVICE, INTERFACE, ENDPOINT, OTHER };
 
-  scoped_refptr<UsbDevice> device() const;
-  PlatformUsbDeviceHandle handle() const { return handle_; }
+  virtual scoped_refptr<UsbDevice> GetDevice() const = 0;
 
   // Notifies UsbDevice to drop the reference of this object; cancels all the
   // flying transfers.
   // It is possible that the object has no other reference after this call. So
   // if it is called using a raw pointer, it could be invalidated.
   // The platform device handle will be closed when UsbDeviceHandle destructs.
-  virtual void Close();
+  virtual void Close() = 0;
 
   // Device manipulation operations. These methods are blocking and must be
   // called on FILE thread.
-  virtual bool ClaimInterface(const int interface_number);
-  virtual bool ReleaseInterface(const int interface_number);
+  virtual bool ClaimInterface(const int interface_number) = 0;
+  virtual bool ReleaseInterface(const int interface_number) = 0;
   virtual bool SetInterfaceAlternateSetting(const int interface_number,
-                                            const int alternate_setting);
-  virtual bool ResetDevice();
-  virtual bool GetSerial(base::string16* serial);
+                                            const int alternate_setting) = 0;
+  virtual bool ResetDevice() = 0;
+  virtual bool GetSerial(base::string16* serial) = 0;
 
   // Async IO. Can be called on any thread.
   virtual void ControlTransfer(const UsbEndpointDirection direction,
@@ -85,21 +70,21 @@ class USB_SERVICE_EXPORT UsbDeviceHandle
                                net::IOBuffer* buffer,
                                const size_t length,
                                const unsigned int timeout,
-                               const UsbTransferCallback& callback);
+                               const UsbTransferCallback& callback) = 0;
 
   virtual void BulkTransfer(const UsbEndpointDirection direction,
                             const uint8 endpoint,
                             net::IOBuffer* buffer,
                             const size_t length,
                             const unsigned int timeout,
-                            const UsbTransferCallback& callback);
+                            const UsbTransferCallback& callback) = 0;
 
   virtual void InterruptTransfer(const UsbEndpointDirection direction,
                                  const uint8 endpoint,
                                  net::IOBuffer* buffer,
                                  const size_t length,
                                  const unsigned int timeout,
-                                 const UsbTransferCallback& callback);
+                                 const UsbTransferCallback& callback) = 0;
 
   virtual void IsochronousTransfer(const UsbEndpointDirection direction,
                                    const uint8 endpoint,
@@ -108,75 +93,14 @@ class USB_SERVICE_EXPORT UsbDeviceHandle
                                    const unsigned int packets,
                                    const unsigned int packet_length,
                                    const unsigned int timeout,
-                                   const UsbTransferCallback& callback);
+                                   const UsbTransferCallback& callback) = 0;
 
  protected:
   friend class base::RefCountedThreadSafe<UsbDeviceHandle>;
-  friend class UsbDeviceImpl;
-
-  // This constructor is called by UsbDevice.
-  UsbDeviceHandle(scoped_refptr<UsbContext> context,
-                  UsbDevice* device,
-                  PlatformUsbDeviceHandle handle,
-                  scoped_refptr<UsbConfigDescriptor> interfaces);
-
-  // This constructor variant is for use in testing only.
-  UsbDeviceHandle();
-  virtual ~UsbDeviceHandle();
-
-  UsbDevice* device_;
-
- private:
-  friend void HandleTransferCompletion(PlatformUsbTransferHandle handle);
-
-  class InterfaceClaimer;
-  struct Transfer;
-
-  // 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);
-
-  // 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(PlatformUsbTransferHandle handle,
-                      UsbTransferType transfer_type,
-                      net::IOBuffer* buffer,
-                      const size_t length,
-                      scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
-                      const UsbTransferCallback& callback);
-
-  // Invokes the callbacks associated with a given transfer, and removes it from
-  // the in-flight transfer set.
-  void TransferComplete(PlatformUsbTransferHandle transfer);
-
-  // Informs the object to drop internal references.
-  void InternalClose();
-
-  PlatformUsbDeviceHandle handle_;
-
-  scoped_refptr<UsbConfigDescriptor> interfaces_;
-
-  typedef std::map<int, scoped_refptr<InterfaceClaimer> > ClaimedInterfaceMap;
-  ClaimedInterfaceMap claimed_interfaces_;
-
-  typedef std::map<PlatformUsbTransferHandle, Transfer> TransferMap;
-  TransferMap 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_;
+  UsbDeviceHandle() {};
 
-  base::ThreadChecker thread_checker_;
+  virtual ~UsbDeviceHandle() {};
 
   DISALLOW_COPY_AND_ASSIGN(UsbDeviceHandle);
 };
diff --git a/components/usb_service/usb_device_handle.cc b/components/usb_service/usb_device_handle_impl.cc
index f0f368e..e3b8987 100644
--- a/components/usb_service/usb_device_handle.cc
+++ b/components/usb_service/usb_device_handle_impl.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "components/usb_service/usb_device_handle.h"
+#include "components/usb_service/usb_device_handle_impl.h"
 
 #include <algorithm>
 #include <vector>
@@ -12,7 +12,7 @@
 #include "base/strings/string16.h"
 #include "base/synchronization/lock.h"
 #include "components/usb_service/usb_context.h"
-#include "components/usb_service/usb_device.h"
+#include "components/usb_service/usb_device_impl.h"
 #include "components/usb_service/usb_interface.h"
 #include "components/usb_service/usb_service.h"
 #include "content/public/browser/browser_thread.h"
@@ -113,17 +113,17 @@ PlatformTransferCompletionCallback(PlatformUsbTransferHandle transfer) {
 
 void HandleTransferCompletion(PlatformUsbTransferHandle transfer) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
-  UsbDeviceHandle* const device_handle =
-      reinterpret_cast<UsbDeviceHandle*>(transfer->user_data);
+  UsbDeviceHandleImpl* const device_handle =
+      reinterpret_cast<UsbDeviceHandleImpl*>(transfer->user_data);
   CHECK(device_handle) << "Device handle is closed before transfer finishes.";
   device_handle->TransferComplete(transfer);
   libusb_free_transfer(transfer);
 }
 
-class UsbDeviceHandle::InterfaceClaimer
-    : public base::RefCountedThreadSafe<UsbDeviceHandle::InterfaceClaimer> {
+class UsbDeviceHandleImpl::InterfaceClaimer
+    : public base::RefCountedThreadSafe<UsbDeviceHandleImpl::InterfaceClaimer> {
  public:
-  InterfaceClaimer(const scoped_refptr<UsbDeviceHandle> handle,
+  InterfaceClaimer(const scoped_refptr<UsbDeviceHandleImpl> handle,
                    const int interface_number);
 
   bool Claim() const;
@@ -138,52 +138,53 @@ class UsbDeviceHandle::InterfaceClaimer
   friend class base::RefCountedThreadSafe<InterfaceClaimer>;
   ~InterfaceClaimer();
 
-  const scoped_refptr<UsbDeviceHandle> handle_;
+  const scoped_refptr<UsbDeviceHandleImpl> handle_;
   const int interface_number_;
   int alternate_setting_;
 
   DISALLOW_COPY_AND_ASSIGN(InterfaceClaimer);
 };
 
-UsbDeviceHandle::InterfaceClaimer::InterfaceClaimer(
-    const scoped_refptr<UsbDeviceHandle> handle,
+UsbDeviceHandleImpl::InterfaceClaimer::InterfaceClaimer(
+    const scoped_refptr<UsbDeviceHandleImpl> handle,
     const int interface_number)
     : handle_(handle),
       interface_number_(interface_number),
       alternate_setting_(0) {
 }
 
-UsbDeviceHandle::InterfaceClaimer::~InterfaceClaimer() {
+UsbDeviceHandleImpl::InterfaceClaimer::~InterfaceClaimer() {
   libusb_release_interface(handle_->handle(), interface_number_);
 }
 
-bool UsbDeviceHandle::InterfaceClaimer::Claim() const {
+bool UsbDeviceHandleImpl::InterfaceClaimer::Claim() const {
   return libusb_claim_interface(handle_->handle(), interface_number_) == 0;
 }
 
-struct UsbDeviceHandle::Transfer {
+struct UsbDeviceHandleImpl::Transfer {
   Transfer();
   ~Transfer();
 
   UsbTransferType transfer_type;
   scoped_refptr<net::IOBuffer> buffer;
-  scoped_refptr<UsbDeviceHandle::InterfaceClaimer> claimed_interface;
+  scoped_refptr<UsbDeviceHandleImpl::InterfaceClaimer> claimed_interface;
   scoped_refptr<base::MessageLoopProxy> message_loop_proxy;
   size_t length;
   UsbTransferCallback callback;
 };
 
-UsbDeviceHandle::Transfer::Transfer()
+UsbDeviceHandleImpl::Transfer::Transfer()
     : transfer_type(USB_TRANSFER_CONTROL), length(0) {
 }
 
-UsbDeviceHandle::Transfer::~Transfer() {
+UsbDeviceHandleImpl::Transfer::~Transfer() {
 }
 
-UsbDeviceHandle::UsbDeviceHandle(scoped_refptr<UsbContext> context,
-                                 UsbDevice* device,
-                                 PlatformUsbDeviceHandle handle,
-                                 scoped_refptr<UsbConfigDescriptor> interfaces)
+UsbDeviceHandleImpl::UsbDeviceHandleImpl(
+    scoped_refptr<UsbContext> context,
+    UsbDeviceImpl* device,
+    PlatformUsbDeviceHandle handle,
+    scoped_refptr<UsbConfigDescriptor> interfaces)
     : device_(device),
       handle_(handle),
       interfaces_(interfaces),
@@ -193,27 +194,24 @@ UsbDeviceHandle::UsbDeviceHandle(scoped_refptr<UsbContext> context,
   DCHECK(interfaces_) << "Unabled to list interfaces";
 }
 
-UsbDeviceHandle::UsbDeviceHandle() : device_(NULL), handle_(NULL) {
-}
-
-UsbDeviceHandle::~UsbDeviceHandle() {
+UsbDeviceHandleImpl::~UsbDeviceHandleImpl() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   libusb_close(handle_);
   handle_ = NULL;
 }
 
-scoped_refptr<UsbDevice> UsbDeviceHandle::device() const {
-  return device_;
+scoped_refptr<UsbDevice> UsbDeviceHandleImpl::GetDevice() const {
+  return static_cast<UsbDevice*>(device_);
 }
 
-void UsbDeviceHandle::Close() {
+void UsbDeviceHandleImpl::Close() {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (device_)
     device_->Close(this);
 }
 
-void UsbDeviceHandle::TransferComplete(PlatformUsbTransferHandle handle) {
+void UsbDeviceHandleImpl::TransferComplete(PlatformUsbTransferHandle handle) {
   DCHECK(ContainsKey(transfers_, handle)) << "Missing transfer completed";
 
   Transfer transfer = transfers_[handle];
@@ -236,7 +234,7 @@ void UsbDeviceHandle::TransferComplete(PlatformUsbTransferHandle handle) {
         CHECK(transfer.length >= LIBUSB_CONTROL_SETUP_SIZE)
             << "buffer was not correctly set: too small for the control header";
 
-        if (transfer.length >= (LIBUSB_CONTROL_SETUP_SIZE + actual_length))  {
+        if (transfer.length >= (LIBUSB_CONTROL_SETUP_SIZE + actual_length)) {
           // If the payload is zero bytes long, pad out the allocated buffer
           // size to one byte so that an IOBuffer of that size can be allocated.
           scoped_refptr<net::IOBuffer> resized_buffer =
@@ -297,7 +295,7 @@ void UsbDeviceHandle::TransferComplete(PlatformUsbTransferHandle handle) {
   transfer.claimed_interface = NULL;
 }
 
-bool UsbDeviceHandle::ClaimInterface(const int interface_number) {
+bool UsbDeviceHandleImpl::ClaimInterface(const int interface_number) {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!device_)
     return false;
@@ -315,7 +313,7 @@ bool UsbDeviceHandle::ClaimInterface(const int interface_number) {
   return false;
 }
 
-bool UsbDeviceHandle::ReleaseInterface(const int interface_number) {
+bool UsbDeviceHandleImpl::ReleaseInterface(const int interface_number) {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!device_)
     return false;
@@ -336,7 +334,7 @@ bool UsbDeviceHandle::ReleaseInterface(const int interface_number) {
   return true;
 }
 
-bool UsbDeviceHandle::SetInterfaceAlternateSetting(
+bool UsbDeviceHandleImpl::SetInterfaceAlternateSetting(
     const int interface_number,
     const int alternate_setting) {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ -355,7 +353,7 @@ bool UsbDeviceHandle::SetInterfaceAlternateSetting(
   return false;
 }
 
-bool UsbDeviceHandle::ResetDevice() {
+bool UsbDeviceHandleImpl::ResetDevice() {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!device_)
     return false;
@@ -363,7 +361,7 @@ bool UsbDeviceHandle::ResetDevice() {
   return libusb_reset_device(handle_) == 0;
 }
 
-bool UsbDeviceHandle::GetSerial(base::string16* serial) {
+bool UsbDeviceHandleImpl::GetSerial(base::string16* serial) {
   DCHECK(thread_checker_.CalledOnValidThread());
   PlatformUsbDevice device = libusb_get_device(handle_);
   libusb_device_descriptor desc;
@@ -411,16 +409,17 @@ bool UsbDeviceHandle::GetSerial(base::string16* serial) {
   return false;
 }
 
-void UsbDeviceHandle::ControlTransfer(const UsbEndpointDirection direction,
-                                      const TransferRequestType request_type,
-                                      const TransferRecipient recipient,
-                                      const uint8 request,
-                                      const uint16 value,
-                                      const uint16 index,
-                                      net::IOBuffer* buffer,
-                                      const size_t length,
-                                      const unsigned int timeout,
-                                      const UsbTransferCallback& callback) {
+void UsbDeviceHandleImpl::ControlTransfer(
+    const UsbEndpointDirection direction,
+    const TransferRequestType request_type,
+    const TransferRecipient recipient,
+    const uint8 request,
+    const uint16 value,
+    const uint16 index,
+    net::IOBuffer* buffer,
+    const size_t length,
+    const unsigned int timeout,
+    const UsbTransferCallback& callback) {
   if (!device_) {
     callback.Run(USB_TRANSFER_DISCONNECT, buffer, 0);
     return;
@@ -455,7 +454,7 @@ void UsbDeviceHandle::ControlTransfer(const UsbEndpointDirection direction,
 
   BrowserThread::PostTask(BrowserThread::FILE,
                           FROM_HERE,
-                          base::Bind(&UsbDeviceHandle::SubmitTransfer,
+                          base::Bind(&UsbDeviceHandleImpl::SubmitTransfer,
                                      this,
                                      transfer,
                                      USB_TRANSFER_CONTROL,
@@ -465,12 +464,12 @@ void UsbDeviceHandle::ControlTransfer(const UsbEndpointDirection direction,
                                      callback));
 }
 
-void UsbDeviceHandle::BulkTransfer(const UsbEndpointDirection direction,
-                                   const uint8 endpoint,
-                                   net::IOBuffer* buffer,
-                                   const size_t length,
-                                   const unsigned int timeout,
-                                   const UsbTransferCallback& callback) {
+void UsbDeviceHandleImpl::BulkTransfer(const UsbEndpointDirection direction,
+                                       const uint8 endpoint,
+                                       net::IOBuffer* buffer,
+                                       const size_t length,
+                                       const unsigned int timeout,
+                                       const UsbTransferCallback& callback) {
   if (!device_) {
     callback.Run(USB_TRANSFER_DISCONNECT, buffer, 0);
     return;
@@ -489,7 +488,7 @@ void UsbDeviceHandle::BulkTransfer(const UsbEndpointDirection direction,
 
   BrowserThread::PostTask(BrowserThread::FILE,
                           FROM_HERE,
-                          base::Bind(&UsbDeviceHandle::SubmitTransfer,
+                          base::Bind(&UsbDeviceHandleImpl::SubmitTransfer,
                                      this,
                                      transfer,
                                      USB_TRANSFER_BULK,
@@ -499,12 +498,13 @@ void UsbDeviceHandle::BulkTransfer(const UsbEndpointDirection direction,
                                      callback));
 }
 
-void UsbDeviceHandle::InterruptTransfer(const UsbEndpointDirection direction,
-                                        const uint8 endpoint,
-                                        net::IOBuffer* buffer,
-                                        const size_t length,
-                                        const unsigned int timeout,
-                                        const UsbTransferCallback& callback) {
+void UsbDeviceHandleImpl::InterruptTransfer(
+    const UsbEndpointDirection direction,
+    const uint8 endpoint,
+    net::IOBuffer* buffer,
+    const size_t length,
+    const unsigned int timeout,
+    const UsbTransferCallback& callback) {
   if (!device_) {
     callback.Run(USB_TRANSFER_DISCONNECT, buffer, 0);
     return;
@@ -522,7 +522,7 @@ void UsbDeviceHandle::InterruptTransfer(const UsbEndpointDirection direction,
                                  timeout);
   BrowserThread::PostTask(BrowserThread::FILE,
                           FROM_HERE,
-                          base::Bind(&UsbDeviceHandle::SubmitTransfer,
+                          base::Bind(&UsbDeviceHandleImpl::SubmitTransfer,
                                      this,
                                      transfer,
                                      USB_TRANSFER_INTERRUPT,
@@ -532,14 +532,15 @@ void UsbDeviceHandle::InterruptTransfer(const UsbEndpointDirection direction,
                                      callback));
 }
 
-void UsbDeviceHandle::IsochronousTransfer(const UsbEndpointDirection direction,
-                                          const uint8 endpoint,
-                                          net::IOBuffer* buffer,
-                                          const size_t length,
-                                          const unsigned int packets,
-                                          const unsigned int packet_length,
-                                          const unsigned int timeout,
-                                          const UsbTransferCallback& callback) {
+void UsbDeviceHandleImpl::IsochronousTransfer(
+    const UsbEndpointDirection direction,
+    const uint8 endpoint,
+    net::IOBuffer* buffer,
+    const size_t length,
+    const unsigned int packets,
+    const unsigned int packet_length,
+    const unsigned int timeout,
+    const UsbTransferCallback& callback) {
   if (!device_) {
     callback.Run(USB_TRANSFER_DISCONNECT, buffer, 0);
     return;
@@ -564,7 +565,7 @@ void UsbDeviceHandle::IsochronousTransfer(const UsbEndpointDirection direction,
 
   BrowserThread::PostTask(BrowserThread::FILE,
                           FROM_HERE,
-                          base::Bind(&UsbDeviceHandle::SubmitTransfer,
+                          base::Bind(&UsbDeviceHandleImpl::SubmitTransfer,
                                      this,
                                      transfer,
                                      USB_TRANSFER_ISOCHRONOUS,
@@ -574,7 +575,7 @@ void UsbDeviceHandle::IsochronousTransfer(const UsbEndpointDirection direction,
                                      callback));
 }
 
-void UsbDeviceHandle::RefreshEndpointMap() {
+void UsbDeviceHandleImpl::RefreshEndpointMap() {
   DCHECK(thread_checker_.CalledOnValidThread());
   endpoint_map_.clear();
   for (ClaimedInterfaceMap::iterator it = claimed_interfaces_.begin();
@@ -591,15 +592,15 @@ void UsbDeviceHandle::RefreshEndpointMap() {
   }
 }
 
-scoped_refptr<UsbDeviceHandle::InterfaceClaimer>
-UsbDeviceHandle::GetClaimedInterfaceForEndpoint(unsigned char endpoint) {
+scoped_refptr<UsbDeviceHandleImpl::InterfaceClaimer>
+UsbDeviceHandleImpl::GetClaimedInterfaceForEndpoint(unsigned char endpoint) {
   unsigned char address = endpoint & LIBUSB_ENDPOINT_ADDRESS_MASK;
   if (ContainsKey(endpoint_map_, address))
     return claimed_interfaces_[endpoint_map_[address]];
   return NULL;
 }
 
-void UsbDeviceHandle::SubmitTransfer(
+void UsbDeviceHandleImpl::SubmitTransfer(
     PlatformUsbTransferHandle handle,
     UsbTransferType transfer_type,
     net::IOBuffer* buffer,
@@ -635,7 +636,7 @@ void UsbDeviceHandle::SubmitTransfer(
   }
 }
 
-void UsbDeviceHandle::InternalClose() {
+void UsbDeviceHandleImpl::InternalClose() {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!device_)
     return;
diff --git a/components/usb_service/usb_device_handle_impl.h b/components/usb_service/usb_device_handle_impl.h
new file mode 100644
index 0000000..0af9f3a
--- /dev/null
+++ b/components/usb_service/usb_device_handle_impl.h
@@ -0,0 +1,156 @@
+// 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 COMPONENTS_USB_SERVICE_USB_DEVICE_HANDLE_IMPL_H_
+#define COMPONENTS_USB_SERVICE_USB_DEVICE_HANDLE_IMPL_H_
+
+#include <map>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
+#include "base/strings/string16.h"
+#include "base/threading/thread_checker.h"
+#include "components/usb_service/usb_device_handle.h"
+#include "components/usb_service/usb_interface.h"
+#include "net/base/io_buffer.h"
+
+struct libusb_device_handle;
+struct libusb_iso_packet_descriptor;
+struct libusb_transfer;
+
+namespace base {
+class MessageLoopProxy;
+}
+
+namespace usb_service {
+
+class UsbContext;
+class 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:
+  virtual scoped_refptr<UsbDevice> GetDevice() const OVERRIDE;
+  virtual void Close() OVERRIDE;
+  virtual bool ClaimInterface(const int interface_number) OVERRIDE;
+  virtual bool ReleaseInterface(const int interface_number) OVERRIDE;
+  virtual bool SetInterfaceAlternateSetting(
+      const int interface_number,
+      const int alternate_setting) OVERRIDE;
+  virtual bool ResetDevice() OVERRIDE;
+  virtual bool GetSerial(base::string16* serial) OVERRIDE;
+  virtual void ControlTransfer(const UsbEndpointDirection direction,
+                               const TransferRequestType request_type,
+                               const TransferRecipient recipient,
+                               const uint8 request,
+                               const uint16 value,
+                               const uint16 index,
+                               net::IOBuffer* buffer,
+                               const size_t length,
+                               const unsigned int timeout,
+                               const UsbTransferCallback& callback) OVERRIDE;
+
+  virtual void BulkTransfer(const UsbEndpointDirection direction,
+                            const uint8 endpoint,
+                            net::IOBuffer* buffer,
+                            const size_t length,
+                            const unsigned int timeout,
+                            const UsbTransferCallback& callback) OVERRIDE;
+
+  virtual void InterruptTransfer(const UsbEndpointDirection direction,
+                                 const uint8 endpoint,
+                                 net::IOBuffer* buffer,
+                                 const size_t length,
+                                 const unsigned int timeout,
+                                 const UsbTransferCallback& callback) OVERRIDE;
+
+  virtual void IsochronousTransfer(
+      const UsbEndpointDirection direction,
+      const uint8 endpoint,
+      net::IOBuffer* buffer,
+      const size_t length,
+      const unsigned int packets,
+      const unsigned int packet_length,
+      const unsigned int timeout,
+      const UsbTransferCallback& callback) OVERRIDE;
+
+  PlatformUsbDeviceHandle handle() const { return handle_; }
+
+ protected:
+  friend class UsbDeviceImpl;
+
+  // This constructor is called by UsbDevice.
+  UsbDeviceHandleImpl(scoped_refptr<UsbContext> context,
+                      UsbDeviceImpl* device,
+                      PlatformUsbDeviceHandle handle,
+                      scoped_refptr<UsbConfigDescriptor> interfaces);
+
+  virtual ~UsbDeviceHandleImpl();
+
+ private:
+  friend void HandleTransferCompletion(PlatformUsbTransferHandle handle);
+
+  class InterfaceClaimer;
+  struct Transfer;
+
+  // 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);
+
+  // 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(PlatformUsbTransferHandle handle,
+                      UsbTransferType transfer_type,
+                      net::IOBuffer* buffer,
+                      const size_t length,
+                      scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
+                      const UsbTransferCallback& callback);
+
+  // Invokes the callbacks associated with a given transfer, and removes it from
+  // the in-flight transfer set.
+  void TransferComplete(PlatformUsbTransferHandle transfer);
+
+  // Informs the object to drop internal references.
+  void InternalClose();
+
+  UsbDeviceImpl* device_;
+
+  PlatformUsbDeviceHandle handle_;
+
+  scoped_refptr<UsbConfigDescriptor> interfaces_;
+
+  typedef std::map<int, scoped_refptr<InterfaceClaimer> > ClaimedInterfaceMap;
+  ClaimedInterfaceMap claimed_interfaces_;
+
+  typedef std::map<PlatformUsbTransferHandle, Transfer> TransferMap;
+  TransferMap 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_;
+
+  base::ThreadChecker thread_checker_;
+
+  DISALLOW_COPY_AND_ASSIGN(UsbDeviceHandleImpl);
+};
+
+}  // namespace usb_service
+
+#endif  // COMPONENTS_USB_SERVICE_USB_DEVICE_HANDLE_IMPL_H_
diff --git a/components/usb_service/usb_device_impl.cc b/components/usb_service/usb_device_impl.cc
index f1d69a3..43c8c66 100644
--- a/components/usb_service/usb_device_impl.cc
+++ b/components/usb_service/usb_device_impl.cc
@@ -8,7 +8,7 @@
 
 #include "base/stl_util.h"
 #include "components/usb_service/usb_context.h"
-#include "components/usb_service/usb_device_handle.h"
+#include "components/usb_service/usb_device_handle_impl.h"
 #include "components/usb_service/usb_interface_impl.h"
 #include "content/public/browser/browser_thread.h"
 #include "third_party/libusb/src/libusb/libusb.h"
@@ -98,8 +98,8 @@ scoped_refptr<UsbDeviceHandle> UsbDeviceImpl::Open() {
     scoped_refptr<UsbConfigDescriptor> interfaces = ListInterfaces();
     if (!interfaces)
       return NULL;
-    scoped_refptr<UsbDeviceHandle> device_handle =
-        new UsbDeviceHandle(context_, this, handle, interfaces);
+    scoped_refptr<UsbDeviceHandleImpl> device_handle =
+        new UsbDeviceHandleImpl(context_, this, handle, interfaces);
     handles_.push_back(device_handle);
     return device_handle;
   }
@@ -136,12 +136,8 @@ void UsbDeviceImpl::OnDisconnect() {
   DCHECK(thread_checker_.CalledOnValidThread());
   HandlesVector handles;
   swap(handles, handles_);
-  for (std::vector<scoped_refptr<UsbDeviceHandle> >::iterator it =
-           handles.begin();
-       it != handles.end();
-       ++it) {
+  for (HandlesVector::iterator it = handles.begin(); it != handles.end(); ++it)
     (*it)->InternalClose();
-  }
 }
 
 }  // namespace usb_service
diff --git a/components/usb_service/usb_device_impl.h b/components/usb_service/usb_device_impl.h
index 5a7cc24..db84f5e 100644
--- a/components/usb_service/usb_device_impl.h
+++ b/components/usb_service/usb_device_impl.h
@@ -17,7 +17,7 @@ struct libusb_config_descriptor;
 
 namespace usb_service {
 
-class UsbDeviceHandle;
+class UsbDeviceHandleImpl;
 class UsbContext;
 
 typedef libusb_device* PlatformUsbDevice;
@@ -58,7 +58,7 @@ class UsbDeviceImpl : public UsbDevice {
   scoped_refptr<UsbContext> context_;
 
   // Opened handles.
-  typedef std::vector<scoped_refptr<UsbDeviceHandle> > HandlesVector;
+  typedef std::vector<scoped_refptr<UsbDeviceHandleImpl> > HandlesVector;
   HandlesVector handles_;
 
   DISALLOW_COPY_AND_ASSIGN(UsbDeviceImpl);