Consolidate/cleanup event cracking code; single out GdkEvents.

ui/base/x/events_x.cc

+// Copyright (c) 2011 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.
+
+#include "ui/base/events.h"
+
+#include <X11/extensions/XInput2.h>
+
+#include "base/logging.h"
+#include "ui/base/keycodes/keyboard_code_conversion_x.h"
+#include "ui/base/touchui/touch_factory.h"
+#include "ui/gfx/point.h"
+
+namespace {
+
+// Scroll amount for each wheelscroll event. 53 is also the value used for GTK+.
+static int kWheelScrollAmount = 53;
+
+int GetEventFlagsFromXState(unsigned int state) {
+  int flags = 0;
+  if (state & ControlMask)
+    flags |= ui::EF_CONTROL_DOWN;
+  if (state & ShiftMask)
+    flags |= ui::EF_SHIFT_DOWN;
+  if (state & Mod1Mask)
+    flags |= ui::EF_ALT_DOWN;
+  if (state & LockMask)
+    flags |= ui::EF_CAPS_LOCK_DOWN;
+  if (state & Button1Mask)
+    flags |= ui::EF_LEFT_BUTTON_DOWN;
+  if (state & Button2Mask)
+    flags |= ui::EF_MIDDLE_BUTTON_DOWN;
+  if (state & Button3Mask)
+    flags |= ui::EF_RIGHT_BUTTON_DOWN;
+  return flags;
+}
+
+// Get the event flag for the button in XButtonEvent. During a ButtonPress
+// event, |state| in XButtonEvent does not include the button that has just been
+// pressed. Instead |state| contains flags for the buttons (if any) that had
+// already been pressed before the current button, and |button| stores the most
+// current pressed button. So, if you press down left mouse button, and while
+// pressing it down, press down the right mouse button, then for the latter
+// event, |state| would have Button1Mask set but not Button3Mask, and |button|
+// would be 3.
+int GetEventFlagsForButton(int button) {
+  switch (button) {
+    case 1:
+      return ui::EF_LEFT_BUTTON_DOWN;
+    case 2:
+      return ui::EF_MIDDLE_BUTTON_DOWN;
+    case 3:
+      return ui::EF_RIGHT_BUTTON_DOWN;
+  }
+  DLOG(WARNING) << "Unexpected button (" << button << ") received.";
+  return 0;
+}
+
+int GetButtonMaskForX2Event(XIDeviceEvent* xievent) {
+  int buttonflags = 0;
+  for (int i = 0; i < 8 * xievent->buttons.mask_len; i++) {
+    if (XIMaskIsSet(xievent->buttons.mask, i)) {
+      buttonflags |= GetEventFlagsForButton(i);
+    }
+  }
+  return buttonflags;
+}
+
+ui::EventType GetTouchEventType(const ui::NativeEvent& native_event) {
+  XGenericEventCookie* cookie = &native_event->xcookie;
+  DCHECK_EQ(cookie->evtype, XI_Motion);
+
+  // Note: We will not generate a _STATIONARY event here. It will be created,
+  // when necessary, by a RWHVV.
+  // TODO(sad): When should _CANCELLED be generated?
+
+  ui::TouchFactory* factory = ui::TouchFactory::GetInstance();
+  float slot;
+  if (!factory->ExtractTouchParam(*native_event, ui::TouchFactory::TP_SLOT_ID,
+                                  &slot))
+    return ui::ET_UNKNOWN;
+
+  if (!factory->IsSlotUsed(slot)) {
+    // This is a new touch point.
+    return ui::ET_TOUCH_PRESSED;
+  }
+
+  float tracking;
+  if (!factory->ExtractTouchParam(*native_event,
+                                  ui::TouchFactory::TP_TRACKING_ID, &tracking))
+    return ui::ET_UNKNOWN;
+
+  if (tracking == 0l) {
+    // The touch point has been released.
+    return ui::ET_TOUCH_RELEASED;
+  }
+
+  return ui::ET_TOUCH_MOVED;
+}
+
+}  // namespace
+
+namespace ui {
+
+EventType EventTypeFromNative(const NativeEvent& native_event) {
+  switch (native_event->type) {
+    case KeyPress:
+      return ET_KEY_PRESSED;
+    case KeyRelease:
+      return ET_KEY_RELEASED;
+    case ButtonPress:
+      if (native_event->xbutton.button == 4 ||
+          native_event->xbutton.button == 5)
+        return ET_MOUSEWHEEL;
+      return ET_MOUSE_PRESSED;
+    case ButtonRelease:
+      if (native_event->xbutton.button == 4 ||
+          native_event->xbutton.button == 5)
+        return ET_MOUSEWHEEL;
+      return ET_MOUSE_RELEASED;
+    case MotionNotify:
+      if (native_event->xmotion.state &
+          (Button1Mask | Button2Mask | Button3Mask))
+        return ET_MOUSE_DRAGGED;
+      return ET_MOUSE_MOVED;
+    case GenericEvent: {
+      XIDeviceEvent* xievent =
+          static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+      if (TouchFactory::GetInstance()->IsTouchDevice(xievent->sourceid))
+        return GetTouchEventType(native_event);
+      switch (xievent->evtype) {
+        case XI_ButtonPress:
+          return (xievent->detail == 4 || xievent->detail == 5) ?
+              ET_MOUSEWHEEL : ET_MOUSE_PRESSED;
+        case XI_ButtonRelease:
+          return (xievent->detail == 4 || xievent->detail == 5) ?
+              ET_MOUSEWHEEL : ET_MOUSE_RELEASED;
+        case XI_Motion:
+          return GetButtonMaskForX2Event(xievent) ?
+              ET_MOUSE_DRAGGED : ET_MOUSE_MOVED;
+      }
+    }
+    default:
+      NOTREACHED();
+      break;
+  }
+  return ET_UNKNOWN;
+}
+
+int EventFlagsFromNative(const NativeEvent& native_event) {
+  switch (native_event->type) {
+    case KeyPress:
+    case KeyRelease:
+      return GetEventFlagsFromXState(native_event->xbutton.state);
+    case ButtonPress:
+    case ButtonRelease:
+      return GetEventFlagsFromXState(native_event->xbutton.state) |
+             GetEventFlagsForButton(native_event->xbutton.button);
+    case MotionNotify:
+      return GetEventFlagsFromXState(native_event->xmotion.state);
+    case GenericEvent: {
+      XIDeviceEvent* xievent =
+          static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+      bool touch =
+          TouchFactory::GetInstance()->IsTouchDevice(xievent->sourceid);
+      switch (xievent->evtype) {
+        case XI_ButtonPress:
+        case XI_ButtonRelease:
+          return GetButtonMaskForX2Event(xievent) |
+                 GetEventFlagsFromXState(xievent->mods.effective) |
+                 (touch ? 0 : GetEventFlagsForButton(xievent->detail));
+        case XI_Motion:
+           return GetButtonMaskForX2Event(xievent) |
+                  GetEventFlagsFromXState(xievent->mods.effective);
+      }
+    }
+  }
+  return 0;
+}
+
+gfx::Point EventLocationFromNative(const NativeEvent& native_event) {
+  switch (native_event->type) {
+    case ButtonPress:
+    case ButtonRelease:
+      return gfx::Point(native_event->xbutton.x, native_event->xbutton.y);
+    case MotionNotify:
+      return gfx::Point(native_event->xmotion.x, native_event->xmotion.y);
+    case GenericEvent: {
+      XIDeviceEvent* xievent =
+          static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+      return gfx::Point(static_cast<int>(xievent->event_x),
+                        static_cast<int>(xievent->event_y));
+    }
+  }
+  return gfx::Point();
+}
+
+KeyboardCode KeyboardCodeFromNative(const NativeEvent& native_event) {
+  return KeyboardCodeFromXKeyEvent(native_event);
+}
+
+bool IsMouseEvent(const NativeEvent& native_event) {
+  if (native_event->type == ButtonPress ||
+      native_event->type == ButtonRelease ||
+      native_event->type == MotionNotify)
+    return true;
+  if (native_event->type == GenericEvent) {
+    XIDeviceEvent* xievent =
+        static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+    return xievent->evtype == XI_ButtonPress ||
+           xievent->evtype == XI_ButtonRelease ||
+           xievent->evtype == XI_Motion;
+  }
+  return false;
+}
+
+int GetMouseWheelOffset(const NativeEvent& native_event) {
+  if (native_event->type == GenericEvent) {
+    XIDeviceEvent* xiev =
+        static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+    return xiev->detail == 4 ? kWheelScrollAmount : -kWheelScrollAmount;
+  }
+  return native_event->xbutton.button == 4 ?
+      kWheelScrollAmount : -kWheelScrollAmount;
+}
+
+}  // namespace ui