src/ui/events/x/events_x.cc

   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 #include "ui/events/event_constants.h"
   6
   7 #include <cmath>
   8 #include <string.h>
   9 #include <X11/extensions/XInput.h>
  10 #include <X11/extensions/XInput2.h>
  11 #include <X11/Xlib.h>
  12
  13 #include "base/logging.h"
  14 #include "base/memory/singleton.h"
  15 #include "base/message_loop/message_pump_x11.h"
  16 #include "ui/events/event_utils.h"
  17 #include "ui/events/keycodes/keyboard_code_conversion_x.h"
  18 #include "ui/events/x/device_data_manager.h"
  19 #include "ui/events/x/device_list_cache_x.h"
  20 #include "ui/events/x/touch_factory_x11.h"
  21 #include "ui/gfx/display.h"
  22 #include "ui/gfx/point.h"
  23 #include "ui/gfx/rect.h"
  24 #include "ui/gfx/screen.h"
  25 #include "ui/gfx/x/x11_atom_cache.h"
  26 #include "ui/gfx/x/x11_types.h"
  27
  28 namespace {
  29
  30 // Scroll amount for each wheelscroll event. 53 is also the value used for GTK+.
  31 const int kWheelScrollAmount = 53;
  32
  33 const int kMinWheelButton = 4;
  34 const int kMaxWheelButton = 7;
  35
  36 // A class to track current modifier state on master device. Only track ctrl,
  37 // alt, shift and caps lock keys currently. The tracked state can then be used
  38 // by floating device.
  39 class XModifierStateWatcher{
  40  public:
  41   static XModifierStateWatcher* GetInstance() {
  42     return Singleton<XModifierStateWatcher>::get();
  43   }
  44
  45   void UpdateStateFromEvent(const base::NativeEvent& native_event) {
  46     // Floating device can't access the modifer state from master device.
  47     // We need to track the states of modifier keys in a singleton for
  48     // floating devices such as touch screen. Issue 106426 is one example
  49     // of why we need the modifier states for floating device.
  50     state_ = native_event->xkey.state;
  51     // master_state is the state before key press. We need to track the
  52     // state after key press for floating device. Currently only ctrl,
  53     // shift, alt and caps lock keys are tracked.
  54     ui::KeyboardCode keyboard_code = ui::KeyboardCodeFromNative(native_event);
  55     unsigned int mask = 0;
  56
  57     switch (keyboard_code) {
  58       case ui::VKEY_CONTROL: {
  59         mask = ControlMask;
  60         break;
  61       }
  62       case ui::VKEY_SHIFT: {
  63         mask = ShiftMask;
  64         break;
  65       }
  66       case ui::VKEY_MENU: {
  67         mask = Mod1Mask;
  68         break;
  69       }
  70       case ui::VKEY_CAPITAL: {
  71         mask = LockMask;
  72         break;
  73       }
  74       default:
  75         break;
  76     }
  77
  78     if (native_event->type == KeyPress)
  79       state_ |= mask;
  80     else
  81       state_ &= ~mask;
  82   }
  83
  84   // Returns the current modifer state in master device. It only contains the
  85   // state of ctrl, shift, alt and caps lock keys.
  86   unsigned int state() { return state_; }
  87
  88  private:
  89   friend struct DefaultSingletonTraits<XModifierStateWatcher>;
  90
  91   XModifierStateWatcher() : state_(0) { }
  92
  93   unsigned int state_;
  94
  95   DISALLOW_COPY_AND_ASSIGN(XModifierStateWatcher);
  96 };
  97
  98 #if defined(USE_XI2_MT)
  99 // Detects if a touch event is a driver-generated 'special event'.
 100 // A 'special event' is a touch event with maximum radius and pressure at
 101 // location (0, 0).
 102 // This needs to be done in a cleaner way: http://crbug.com/169256
 103 bool TouchEventIsGeneratedHack(const base::NativeEvent& native_event) {
 104   XIDeviceEvent* event =
 105       static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 106   CHECK(event->evtype == XI_TouchBegin ||
 107         event->evtype == XI_TouchUpdate ||
 108         event->evtype == XI_TouchEnd);
 109
 110   // Force is normalized to [0, 1].
 111   if (ui::GetTouchForce(native_event) < 1.0f)
 112     return false;
 113
 114   if (ui::EventLocationFromNative(native_event) != gfx::Point())
 115     return false;
 116
 117   // Radius is in pixels, and the valuator is the diameter in pixels.
 118   double radius = ui::GetTouchRadiusX(native_event), min, max;
 119   unsigned int deviceid =
 120       static_cast<XIDeviceEvent*>(native_event->xcookie.data)->sourceid;
 121   if (!ui::DeviceDataManager::GetInstance()->GetDataRange(
 122       deviceid, ui::DeviceDataManager::DT_TOUCH_MAJOR, &min, &max)) {
 123     return false;
 124   }
 125
 126   return radius * 2 == max;
 127 }
 128 #endif
 129
 130 int GetEventFlagsFromXState(unsigned int state) {
 131   int flags = 0;
 132   if (state & ControlMask)
 133     flags |= ui::EF_CONTROL_DOWN;
 134   if (state & ShiftMask)
 135     flags |= ui::EF_SHIFT_DOWN;
 136   if (state & Mod1Mask)
 137     flags |= ui::EF_ALT_DOWN;
 138   if (state & LockMask)
 139     flags |= ui::EF_CAPS_LOCK_DOWN;
 140   if (state & Mod5Mask)
 141     flags |= ui::EF_ALTGR_DOWN;
 142   if (state & Button1Mask)
 143     flags |= ui::EF_LEFT_MOUSE_BUTTON;
 144   if (state & Button2Mask)
 145     flags |= ui::EF_MIDDLE_MOUSE_BUTTON;
 146   if (state & Button3Mask)
 147     flags |= ui::EF_RIGHT_MOUSE_BUTTON;
 148   return flags;
 149 }
 150
 151 // Get the event flag for the button in XButtonEvent. During a ButtonPress
 152 // event, |state| in XButtonEvent does not include the button that has just been
 153 // pressed. Instead |state| contains flags for the buttons (if any) that had
 154 // already been pressed before the current button, and |button| stores the most
 155 // current pressed button. So, if you press down left mouse button, and while
 156 // pressing it down, press down the right mouse button, then for the latter
 157 // event, |state| would have Button1Mask set but not Button3Mask, and |button|
 158 // would be 3.
 159 int GetEventFlagsForButton(int button) {
 160   switch (button) {
 161     case 1:
 162       return ui::EF_LEFT_MOUSE_BUTTON;
 163     case 2:
 164       return ui::EF_MIDDLE_MOUSE_BUTTON;
 165     case 3:
 166       return ui::EF_RIGHT_MOUSE_BUTTON;
 167     default:
 168       return 0;
 169   }
 170 }
 171
 172 int GetButtonMaskForX2Event(XIDeviceEvent* xievent) {
 173   int buttonflags = 0;
 174   for (int i = 0; i < 8 * xievent->buttons.mask_len; i++) {
 175     if (XIMaskIsSet(xievent->buttons.mask, i)) {
 176       int button = (xievent->sourceid == xievent->deviceid) ?
 177                    ui::DeviceDataManager::GetInstance()->GetMappedButton(i) : i;
 178       buttonflags |= GetEventFlagsForButton(button);
 179     }
 180   }
 181   return buttonflags;
 182 }
 183
 184 ui::EventType GetTouchEventType(const base::NativeEvent& native_event) {
 185   XIDeviceEvent* event =
 186       static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 187 #if defined(USE_XI2_MT)
 188   switch(event->evtype) {
 189     case XI_TouchBegin:
 190       return TouchEventIsGeneratedHack(native_event) ? ui::ET_UNKNOWN :
 191                                                        ui::ET_TOUCH_PRESSED;
 192     case XI_TouchUpdate:
 193       return TouchEventIsGeneratedHack(native_event) ? ui::ET_UNKNOWN :
 194                                                        ui::ET_TOUCH_MOVED;
 195     case XI_TouchEnd:
 196       return TouchEventIsGeneratedHack(native_event) ? ui::ET_TOUCH_CANCELLED :
 197                                                        ui::ET_TOUCH_RELEASED;
 198   }
 199 #endif  // defined(USE_XI2_MT)
 200
 201   DCHECK(ui::TouchFactory::GetInstance()->IsTouchDevice(event->sourceid));
 202   switch (event->evtype) {
 203     case XI_ButtonPress:
 204       return ui::ET_TOUCH_PRESSED;
 205     case XI_ButtonRelease:
 206       return ui::ET_TOUCH_RELEASED;
 207     case XI_Motion:
 208       // Should not convert any emulated Motion event from touch device to
 209       // touch event.
 210       if (!(event->flags & XIPointerEmulated) &&
 211           GetButtonMaskForX2Event(event))
 212         return ui::ET_TOUCH_MOVED;
 213       return ui::ET_UNKNOWN;
 214     default:
 215       NOTREACHED();
 216   }
 217   return ui::ET_UNKNOWN;
 218 }
 219
 220 double GetTouchParamFromXEvent(XEvent* xev,
 221                               ui::DeviceDataManager::DataType val,
 222                               double default_value) {
 223   ui::DeviceDataManager::GetInstance()->GetEventData(
 224       *xev, val, &default_value);
 225   return default_value;
 226 }
 227
 228 }  // namespace
 229
 230 namespace ui {
 231
 232 void UpdateDeviceList() {
 233   XDisplay* display = gfx::GetXDisplay();
 234   DeviceListCacheX::GetInstance()->UpdateDeviceList(display);
 235   TouchFactory::GetInstance()->UpdateDeviceList(display);
 236   DeviceDataManager::GetInstance()->UpdateDeviceList(display);
 237 }
 238
 239 EventType EventTypeFromNative(const base::NativeEvent& native_event) {
 240   switch (native_event->type) {
 241     case KeyPress:
 242       return ET_KEY_PRESSED;
 243     case KeyRelease:
 244       return ET_KEY_RELEASED;
 245     case ButtonPress:
 246       if (static_cast<int>(native_event->xbutton.button) >= kMinWheelButton &&
 247           static_cast<int>(native_event->xbutton.button) <= kMaxWheelButton)
 248         return ET_MOUSEWHEEL;
 249       return ET_MOUSE_PRESSED;
 250     case ButtonRelease:
 251       // Drop wheel events; we should've already scrolled on the press.
 252       if (static_cast<int>(native_event->xbutton.button) >= kMinWheelButton &&
 253           static_cast<int>(native_event->xbutton.button) <= kMaxWheelButton)
 254         return ET_UNKNOWN;
 255       return ET_MOUSE_RELEASED;
 256     case MotionNotify:
 257       if (native_event->xmotion.state &
 258           (Button1Mask | Button2Mask | Button3Mask))
 259         return ET_MOUSE_DRAGGED;
 260       return ET_MOUSE_MOVED;
 261     case EnterNotify:
 262       // The standard on Windows is to send a MouseMove event when the mouse
 263       // first enters a window instead of sending a special mouse enter event.
 264       // To be consistent we follow the same style.
 265       return ET_MOUSE_MOVED;
 266     case LeaveNotify:
 267       return ET_MOUSE_EXITED;
 268     case GenericEvent: {
 269       TouchFactory* factory = TouchFactory::GetInstance();
 270       if (!factory->ShouldProcessXI2Event(native_event))
 271         return ET_UNKNOWN;
 272
 273       XIDeviceEvent* xievent =
 274           static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 275
 276       // This check works only for master and floating slave devices. That is
 277       // why it is necessary to check for the XI_Touch* events in the following
 278       // switch statement to account for attached-slave touchscreens.
 279       if (factory->IsTouchDevice(xievent->sourceid))
 280         return GetTouchEventType(native_event);
 281
 282       switch (xievent->evtype) {
 283         case XI_TouchBegin:
 284           return ui::ET_TOUCH_PRESSED;
 285         case XI_TouchUpdate:
 286           return ui::ET_TOUCH_MOVED;
 287         case XI_TouchEnd:
 288           return ui::ET_TOUCH_RELEASED;
 289         case XI_ButtonPress: {
 290           int button = EventButtonFromNative(native_event);
 291           if (button >= kMinWheelButton && button <= kMaxWheelButton)
 292             return ET_MOUSEWHEEL;
 293           return ET_MOUSE_PRESSED;
 294         }
 295         case XI_ButtonRelease: {
 296           int button = EventButtonFromNative(native_event);
 297           // Drop wheel events; we should've already scrolled on the press.
 298           if (button >= kMinWheelButton && button <= kMaxWheelButton)
 299             return ET_UNKNOWN;
 300           return ET_MOUSE_RELEASED;
 301         }
 302         case XI_Motion: {
 303           bool is_cancel;
 304           if (GetFlingData(native_event, NULL, NULL, NULL, NULL, &is_cancel)) {
 305             return is_cancel ? ET_SCROLL_FLING_CANCEL : ET_SCROLL_FLING_START;
 306           } else if (DeviceDataManager::GetInstance()->IsScrollEvent(
 307               native_event)) {
 308             return IsTouchpadEvent(native_event) ? ET_SCROLL : ET_MOUSEWHEEL;
 309           } else if (DeviceDataManager::GetInstance()->IsCMTMetricsEvent(
 310               native_event)) {
 311             return ET_UMA_DATA;
 312           } else if (GetButtonMaskForX2Event(xievent)) {
 313             return ET_MOUSE_DRAGGED;
 314           } else {
 315             return ET_MOUSE_MOVED;
 316           }
 317         }
 318       }
 319     }
 320     default:
 321       break;
 322   }
 323   return ET_UNKNOWN;
 324 }
 325
 326 int EventFlagsFromNative(const base::NativeEvent& native_event) {
 327   switch (native_event->type) {
 328     case KeyPress:
 329     case KeyRelease: {
 330       XModifierStateWatcher::GetInstance()->UpdateStateFromEvent(native_event);
 331       return GetEventFlagsFromXState(native_event->xkey.state);
 332     }
 333     case ButtonPress:
 334     case ButtonRelease: {
 335       int flags = GetEventFlagsFromXState(native_event->xbutton.state);
 336       const EventType type = EventTypeFromNative(native_event);
 337       if (type == ET_MOUSE_PRESSED || type == ET_MOUSE_RELEASED)
 338         flags |= GetEventFlagsForButton(native_event->xbutton.button);
 339       return flags;
 340     }
 341     case EnterNotify:
 342     case LeaveNotify:
 343       return GetEventFlagsFromXState(native_event->xcrossing.state);
 344     case MotionNotify:
 345       return GetEventFlagsFromXState(native_event->xmotion.state);
 346     case GenericEvent: {
 347       XIDeviceEvent* xievent =
 348           static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 349
 350       switch (xievent->evtype) {
 351 #if defined(USE_XI2_MT)
 352         case XI_TouchBegin:
 353         case XI_TouchUpdate:
 354         case XI_TouchEnd:
 355           return GetButtonMaskForX2Event(xievent) |
 356                  GetEventFlagsFromXState(xievent->mods.effective) |
 357                  GetEventFlagsFromXState(
 358                      XModifierStateWatcher::GetInstance()->state());
 359           break;
 360 #endif
 361         case XI_ButtonPress:
 362         case XI_ButtonRelease: {
 363           const bool touch =
 364               TouchFactory::GetInstance()->IsTouchDevice(xievent->sourceid);
 365           int flags = GetButtonMaskForX2Event(xievent) |
 366               GetEventFlagsFromXState(xievent->mods.effective);
 367           if (touch) {
 368             flags |= GetEventFlagsFromXState(
 369                 XModifierStateWatcher::GetInstance()->state());
 370           }
 371
 372           const EventType type = EventTypeFromNative(native_event);
 373           int button = EventButtonFromNative(native_event);
 374           if ((type == ET_MOUSE_PRESSED || type == ET_MOUSE_RELEASED) && !touch)
 375             flags |= GetEventFlagsForButton(button);
 376           return flags;
 377         }
 378         case XI_Motion:
 379            return GetButtonMaskForX2Event(xievent) |
 380                   GetEventFlagsFromXState(xievent->mods.effective);
 381       }
 382     }
 383   }
 384   return 0;
 385 }
 386
 387 base::TimeDelta EventTimeFromNative(const base::NativeEvent& native_event) {
 388   switch(native_event->type) {
 389     case KeyPress:
 390     case KeyRelease:
 391       return base::TimeDelta::FromMilliseconds(native_event->xkey.time);
 392     case ButtonPress:
 393     case ButtonRelease:
 394       return base::TimeDelta::FromMilliseconds(native_event->xbutton.time);
 395       break;
 396     case MotionNotify:
 397       return base::TimeDelta::FromMilliseconds(native_event->xmotion.time);
 398       break;
 399     case EnterNotify:
 400     case LeaveNotify:
 401       return base::TimeDelta::FromMilliseconds(native_event->xcrossing.time);
 402       break;
 403     case GenericEvent: {
 404       double start, end;
 405       double touch_timestamp;
 406       if (GetGestureTimes(native_event, &start, &end)) {
 407         // If the driver supports gesture times, use them.
 408         return base::TimeDelta::FromMicroseconds(end * 1000000);
 409       } else if (DeviceDataManager::GetInstance()->GetEventData(*native_event,
 410                  DeviceDataManager::DT_TOUCH_RAW_TIMESTAMP, &touch_timestamp)) {
 411         return base::TimeDelta::FromMicroseconds(touch_timestamp * 1000000);
 412       } else {
 413         XIDeviceEvent* xide =
 414             static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 415         return base::TimeDelta::FromMilliseconds(xide->time);
 416       }
 417       break;
 418     }
 419   }
 420   NOTREACHED();
 421   return base::TimeDelta();
 422 }
 423
 424 gfx::Point EventLocationFromNative(const base::NativeEvent& native_event) {
 425   switch (native_event->type) {
 426     case EnterNotify:
 427     case LeaveNotify:
 428       return gfx::Point(native_event->xcrossing.x, native_event->xcrossing.y);
 429     case ButtonPress:
 430     case ButtonRelease:
 431       return gfx::Point(native_event->xbutton.x, native_event->xbutton.y);
 432     case MotionNotify:
 433       return gfx::Point(native_event->xmotion.x, native_event->xmotion.y);
 434     case GenericEvent: {
 435       XIDeviceEvent* xievent =
 436           static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 437       return gfx::Point(static_cast<int>(xievent->event_x),
 438                         static_cast<int>(xievent->event_y));
 439     }
 440   }
 441   return gfx::Point();
 442 }
 443
 444 gfx::Point EventSystemLocationFromNative(
 445     const base::NativeEvent& native_event) {
 446   switch (native_event->type) {
 447     case EnterNotify:
 448     case LeaveNotify: {
 449       return gfx::Point(native_event->xcrossing.x_root,
 450                         native_event->xcrossing.y_root);
 451     }
 452     case ButtonPress:
 453     case ButtonRelease: {
 454       return gfx::Point(native_event->xbutton.x_root,
 455                         native_event->xbutton.y_root);
 456     }
 457     case MotionNotify: {
 458       return gfx::Point(native_event->xmotion.x_root,
 459                         native_event->xmotion.y_root);
 460     }
 461     case GenericEvent: {
 462       XIDeviceEvent* xievent =
 463           static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 464       return gfx::Point(xievent->root_x, xievent->root_y);
 465     }
 466   }
 467
 468   return gfx::Point();
 469 }
 470
 471 int EventButtonFromNative(const base::NativeEvent& native_event) {
 472   CHECK_EQ(GenericEvent, native_event->type);
 473   XIDeviceEvent* xievent =
 474       static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 475   int button = xievent->detail;
 476
 477   return (xievent->sourceid == xievent->deviceid) ?
 478          DeviceDataManager::GetInstance()->GetMappedButton(button) : button;
 479 }
 480
 481 KeyboardCode KeyboardCodeFromNative(const base::NativeEvent& native_event) {
 482   return KeyboardCodeFromXKeyEvent(native_event);
 483 }
 484
 485 const char* CodeFromNative(const base::NativeEvent& native_event) {
 486   return CodeFromXEvent(native_event);
 487 }
 488
 489 int GetChangedMouseButtonFlagsFromNative(
 490     const base::NativeEvent& native_event) {
 491   switch (native_event->type) {
 492     case ButtonPress:
 493     case ButtonRelease:
 494       return GetEventFlagsFromXState(native_event->xbutton.state);
 495     case GenericEvent: {
 496       XIDeviceEvent* xievent =
 497           static_cast<XIDeviceEvent*>(native_event->xcookie.data);
 498       switch (xievent->evtype) {
 499         case XI_ButtonPress:
 500         case XI_ButtonRelease:
 501           return GetEventFlagsForButton(EventButtonFromNative(native_event));
 502         default:
 503           break;
 504       }
 505     }
 506     default:
 507       break;
 508   }
 509   return 0;
 510 }
 511
 512 gfx::Vector2d GetMouseWheelOffset(const base::NativeEvent& native_event) {
 513   float x_offset, y_offset;
 514   if (GetScrollOffsets(
 515       native_event, &x_offset, &y_offset, NULL, NULL, NULL)) {
 516     return gfx::Vector2d(static_cast<int>(x_offset),
 517                          static_cast<int>(y_offset));
 518   }
 519
 520   int button = native_event->type == GenericEvent ?
 521       EventButtonFromNative(native_event) : native_event->xbutton.button;
 522
 523   switch (button) {
 524     case 4:
 525       return gfx::Vector2d(0, kWheelScrollAmount);
 526     case 5:
 527       return gfx::Vector2d(0, -kWheelScrollAmount);
 528     case 6:
 529       return gfx::Vector2d(kWheelScrollAmount, 0);
 530     case 7:
 531       return gfx::Vector2d(-kWheelScrollAmount, 0);
 532     default:
 533       return gfx::Vector2d();
 534   }
 535 }
 536
 537 void ClearTouchIdIfReleased(const base::NativeEvent& xev) {
 538   ui::EventType type = ui::EventTypeFromNative(xev);
 539   if (type == ui::ET_TOUCH_CANCELLED ||
 540       type == ui::ET_TOUCH_RELEASED) {
 541     ui::TouchFactory* factory = ui::TouchFactory::GetInstance();
 542     ui::DeviceDataManager* manager = ui::DeviceDataManager::GetInstance();
 543     double tracking_id;
 544     if (manager->GetEventData(
 545         *xev, ui::DeviceDataManager::DT_TOUCH_TRACKING_ID, &tracking_id)) {
 546       factory->ReleaseSlotForTrackingID(tracking_id);
 547     }
 548   }
 549 }
 550
 551 int GetTouchId(const base::NativeEvent& xev) {
 552   double slot = 0;
 553   ui::DeviceDataManager* manager = ui::DeviceDataManager::GetInstance();
 554   double tracking_id;
 555   if (!manager->GetEventData(
 556       *xev, ui::DeviceDataManager::DT_TOUCH_TRACKING_ID, &tracking_id)) {
 557     LOG(ERROR) << "Could not get the tracking ID for the event. Using 0.";
 558   } else {
 559     ui::TouchFactory* factory = ui::TouchFactory::GetInstance();
 560     slot = factory->GetSlotForTrackingID(tracking_id);
 561   }
 562   return slot;
 563 }
 564
 565 float GetTouchRadiusX(const base::NativeEvent& native_event) {
 566   return GetTouchParamFromXEvent(native_event,
 567       ui::DeviceDataManager::DT_TOUCH_MAJOR, 0.0) / 2.0;
 568 }
 569
 570 float GetTouchRadiusY(const base::NativeEvent& native_event) {
 571   return GetTouchParamFromXEvent(native_event,
 572       ui::DeviceDataManager::DT_TOUCH_MINOR, 0.0) / 2.0;
 573 }
 574
 575 float GetTouchAngle(const base::NativeEvent& native_event) {
 576   return GetTouchParamFromXEvent(native_event,
 577       ui::DeviceDataManager::DT_TOUCH_ORIENTATION, 0.0) / 2.0;
 578 }
 579
 580 float GetTouchForce(const base::NativeEvent& native_event) {
 581   double force = 0.0;
 582   force = GetTouchParamFromXEvent(native_event,
 583       ui::DeviceDataManager::DT_TOUCH_PRESSURE, 0.0);
 584   unsigned int deviceid =
 585       static_cast<XIDeviceEvent*>(native_event->xcookie.data)->sourceid;
 586   // Force is normalized to fall into [0, 1]
 587   if (!ui::DeviceDataManager::GetInstance()->NormalizeData(
 588       deviceid, ui::DeviceDataManager::DT_TOUCH_PRESSURE, &force))
 589     force = 0.0;
 590   return force;
 591 }
 592
 593 bool GetScrollOffsets(const base::NativeEvent& native_event,
 594                       float* x_offset,
 595                       float* y_offset,
 596                       float* x_offset_ordinal,
 597                       float* y_offset_ordinal,
 598                       int* finger_count) {
 599   if (!DeviceDataManager::GetInstance()->IsScrollEvent(native_event))
 600     return false;
 601
 602   // Temp values to prevent passing NULLs to DeviceDataManager.
 603   float x_offset_, y_offset_;
 604   float x_offset_ordinal_, y_offset_ordinal_;
 605   int finger_count_;
 606   if (!x_offset)
 607     x_offset = &x_offset_;
 608   if (!y_offset)
 609     y_offset = &y_offset_;
 610   if (!x_offset_ordinal)
 611     x_offset_ordinal = &x_offset_ordinal_;
 612   if (!y_offset_ordinal)
 613     y_offset_ordinal = &y_offset_ordinal_;
 614   if (!finger_count)
 615     finger_count = &finger_count_;
 616
 617   DeviceDataManager::GetInstance()->GetScrollOffsets(
 618       native_event,
 619       x_offset, y_offset,
 620       x_offset_ordinal, y_offset_ordinal,
 621       finger_count);
 622   return true;
 623 }
 624
 625 bool GetFlingData(const base::NativeEvent& native_event,
 626                   float* vx,
 627                   float* vy,
 628                   float* vx_ordinal,
 629                   float* vy_ordinal,
 630                   bool* is_cancel) {
 631   if (!DeviceDataManager::GetInstance()->IsFlingEvent(native_event))
 632     return false;
 633
 634   float vx_, vy_;
 635   float vx_ordinal_, vy_ordinal_;
 636   bool is_cancel_;
 637   if (!vx)
 638     vx = &vx_;
 639   if (!vy)
 640     vy = &vy_;
 641   if (!vx_ordinal)
 642     vx_ordinal = &vx_ordinal_;
 643   if (!vy_ordinal)
 644     vy_ordinal = &vy_ordinal_;
 645   if (!is_cancel)
 646     is_cancel = &is_cancel_;
 647
 648   DeviceDataManager::GetInstance()->GetFlingData(
 649       native_event, vx, vy, vx_ordinal, vy_ordinal, is_cancel);
 650   return true;
 651 }
 652
 653 bool GetGestureTimes(const base::NativeEvent& native_event,
 654                      double* start_time,
 655                      double* end_time) {
 656   if (!DeviceDataManager::GetInstance()->HasGestureTimes(native_event))
 657     return false;
 658
 659   double start_time_, end_time_;
 660   if (!start_time)
 661     start_time = &start_time_;
 662   if (!end_time)
 663     end_time = &end_time_;
 664
 665   DeviceDataManager::GetInstance()->GetGestureTimes(
 666       native_event, start_time, end_time);
 667   return true;
 668 }
 669
 670 void SetNaturalScroll(bool enabled) {
 671   DeviceDataManager::GetInstance()->set_natural_scroll_enabled(enabled);
 672 }
 673
 674 bool IsNaturalScrollEnabled() {
 675   return DeviceDataManager::GetInstance()->natural_scroll_enabled();
 676 }
 677
 678 bool IsTouchpadEvent(const base::NativeEvent& event) {
 679   return DeviceDataManager::GetInstance()->IsTouchpadXInputEvent(event);
 680 }
 681
 682 }  // namespace ui