ui/events/x/device_list_cache_x.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_EVENTS_X_DEVICE_LIST_CACHE_X_H_
   6 #define UI_EVENTS_X_DEVICE_LIST_CACHE_X_H_
   7
   8 #include <X11/extensions/XInput.h>
   9 #include <X11/extensions/XInput2.h>
  10
  11 #include <map>
  12
  13 #include "base/basictypes.h"
  14 #include "ui/events/events_base_export.h"
  15
  16 template <typename T> struct DefaultSingletonTraits;
  17
  18 typedef struct _XDisplay Display;
  19
  20 template <typename T>
  21 struct DeviceList {
  22   DeviceList() : devices(NULL), count(0) {
  23   }
  24   T& operator[] (int x) {
  25     return devices[x];
  26   }
  27   const T& operator[](int x) const { return devices[x]; }
  28   T* devices;
  29   int count;
  30 };
  31
  32 typedef struct DeviceList<XDeviceInfo> XDeviceList;
  33 typedef struct DeviceList<XIDeviceInfo> XIDeviceList;
  34
  35 namespace ui {
  36
  37 // A class to cache the current XInput device list. This minimized the
  38 // round-trip time to the X server whenever such a device list is needed. The
  39 // update function will be called on each incoming XI_HierarchyChanged event.
  40 class EVENTS_BASE_EXPORT DeviceListCacheX {
  41  public:
  42   static DeviceListCacheX* GetInstance();
  43
  44   void UpdateDeviceList(Display* display);
  45
  46   // Returns the list of devices associated with |display|. Uses the old X11
  47   // protocol to get the list of the devices.
  48   const XDeviceList& GetXDeviceList(Display* display);
  49
  50   // Returns the list of devices associated with |display|. Uses the newer
  51   // XINPUT2 protocol to get the list of devices. Before making this call, make
  52   // sure that XInput2 support is available (e.g. by calling
  53   // IsXInput2Available()).
  54   const XIDeviceList& GetXI2DeviceList(Display* display);
  55
  56  private:
  57   friend struct DefaultSingletonTraits<DeviceListCacheX>;
  58
  59   DeviceListCacheX();
  60   ~DeviceListCacheX();
  61
  62   std::map<Display*, XDeviceList> x_dev_list_map_;
  63   std::map<Display*, XIDeviceList> xi_dev_list_map_;
  64
  65   DISALLOW_COPY_AND_ASSIGN(DeviceListCacheX);
  66 };
  67
  68 }  // namespace ui
  69
  70 #endif  // UI_EVENTS_X_DEVICE_LIST_CACHE_X_H_
  71