Clean up HID backend and API.

device/hid/hid_service_linux.h

-// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// 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_HID_HID_SERVICE_LINUX_H_
 #define DEVICE_HID_HID_SERVICE_LINUX_H_
 
 #include <libudev.h>
 
+#include <map>
+#include <string>
+
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_pump_libevent.h"
 #include "device/hid/hid_device_info.h"
+#include "device/hid/hid_platform_resource_bidi_map.h"
 #include "device/hid/hid_service.h"
 
 namespace device {
 
 class HidConnection;
 
 template<typename T, void func(T*)>
 void DiscardReturnType(T* arg) { func(arg); }
 template<typename T, T* func(T*)>
 void DiscardReturnType(T* arg) { func(arg); }
@@ skipping 19 matching lines @@
     DiscardReturnType<udev_monitor, udev_monitor_unref> > UdevMonitorDeleter;
 
 typedef scoped_ptr<udev_device, UdevDeviceDeleter> ScopedUdevDevicePtr;
 typedef scoped_ptr<udev_enumerate, UdevEnumerateDeleter> ScopedUdevEnumeratePtr;
 
 class HidServiceLinux : public HidService,
                         public base::MessagePumpLibevent::Watcher {
  public:
   HidServiceLinux();
 
-  virtual scoped_refptr<HidConnection> Connect(std::string device_id) OVERRIDE;
+  virtual scoped_refptr<HidConnection> Connect(HidDeviceId device_id) OVERRIDE;
 
   // Implements base::MessagePumpLibevent::Watcher
   virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE;
   virtual void OnFileCanWriteWithoutBlocking(int fd) OVERRIDE;
 
  private:
   virtual ~HidServiceLinux();
 
   void Enumerate();
-  void PlatformDeviceAdd(udev_device* device);
-  void PlatformDeviceRemove(udev_device* raw_dev);
+  void PlatformAddDevice(udev_device* device);
+  void PlatformRemoveDevice(udev_device* raw_dev);
 
   scoped_ptr<udev, UdevDeleter> udev_;
   scoped_ptr<udev_monitor, UdevMonitorDeleter> monitor_;
   int monitor_fd_;
   base::MessagePumpLibevent::FileDescriptorWatcher monitor_watcher_;
 
+  // A 1:1 mapping between device ID and system path.
+  HidPlatformResourceBidiMap<std::string> platform_resource_map_;
+
   DISALLOW_COPY_AND_ASSIGN(HidServiceLinux);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_HID_HID_SERVICE_LINUX_H_