Adding a Wayland basic toolkit

ui/wayland/events/wayland_event.h

+// 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.
+
+#ifndef UI_WAYLAND_EVENTS_WAYLAND_EVENT_H_
+#define UI_WAYLAND_EVENTS_WAYLAND_EVENT_H_
+
+#include <linux/input.h>
+#include <stdint.h>
+
+// Wayland event information is being passed in as arguments to the callbacks.
+// (See wayland_input_device.{h,cc} for information on the callbacks and how
+// events are processed.)
+// In order to provide a more generic look for events we wrap these arguments
+// in specific event structs. Then define a WaylandEvent as a union of all
+// types of events that Wayland will send.
+//
+// The following fields are common for most event types and their use is
+// similar:
+// - time:
+//    The time of the event. This should be monotonically increasing.
+// - state:
+//    The value of the button event as given by evdev. This is 0 if button
+//    isn't pressed.
+// - modifiers:
+//    Stores all the keyboard modifiers (Ctrl, Alt, Shift, ...) currently
+//    active. The modifiers are values as defined by xkbcommon.
+
+namespace ui {
+
+// Types of events Wayland will send
+enum WaylandEventType {
+  WAYLAND_BUTTON,
+  WAYLAND_KEY,
+  WAYLAND_MOTION,
+  WAYLAND_POINTER_FOCUS,
+  WAYLAND_KEYBOARD_FOCUS,
+  WAYLAND_GEOMETRY_CHANGE,
+};
+
+// These are the mouse events expected. The event type Wayland sends is an
+// evdev event. The following is the correct mapping from evdev to expected
+// events type.
+enum WaylandEventButtonType {
+  LEFT_BUTTON     = BTN_LEFT,
+  MIDDLE_BUTTON   = BTN_RIGHT,
+  RIGHT_BUTTON    = BTN_MIDDLE,
+  SCROLL_UP       = BTN_SIDE,
+  SCROLL_DOWN     = BTN_EXTRA,
+};
+
+struct WaylandEventButton {
+  WaylandEventType type;
+  uint32_t time;
+  // WaylandEventButtonType defines some of the values button can take
+  uint32_t button;
+  uint32_t state;
+  uint32_t modifiers;
+  int32_t x;
+  int32_t y;
+};
+
+struct WaylandEventKey {
+  WaylandEventType type;
+  uint32_t time;
+  // The raw key value that evdev returns.
+  uint32_t key;
+  // The key symbol returned by processing the raw key using the xkbcommon
+  // library.
+  uint32_t sym;
+  uint32_t state;
+  uint32_t modifiers;
+};
+
+// Triggered when there is a motion event. The motion event is triggered
+// only if there is a window under focus.
+struct WaylandEventMotion {
+  WaylandEventType type;
+  uint32_t time;
+  uint32_t modifiers;
+  int32_t x;
+  int32_t y;
+};
+
+// Triggered when a window enters/exits pointer focus. The state tells us
+// if the window lost focus (state == 0) or gained focus (state != 0).
+struct WaylandEventPointerFocus {
+  WaylandEventType type;
+  uint32_t time;
+  uint32_t state;
+  int32_t x;
+  int32_t y;
+};
+
+// Triggered when a window enters/exits keyboard focus. The state tells us
+// if the window lost focus (state == 0) or gained focus (state != 0).
+struct WaylandEventKeyboardFocus {
+  WaylandEventType type;
+  uint32_t time;
+  uint32_t state;
+  uint32_t modifiers;
+};
+
+// Event triggered when a window's geometry changes. The event contains the
+// position and dimensions of the window.
+struct WaylandEventGeometryChange {
+  WaylandEventType type;
+  uint32_t time;
+  int32_t x;
+  int32_t y;
+  int32_t width;
+  int32_t height;
+};
+
+union WaylandEvent {
+  WaylandEventType            type;
+  WaylandEventButton          button;
+  WaylandEventKey             key;
+  WaylandEventMotion          motion;
+  WaylandEventPointerFocus    pointer_focus;
+  WaylandEventKeyboardFocus   keyboard_focus;
+  WaylandEventGeometryChange  geometry_change;
+};
+
+}  // namespace ui
+
+#endif  // UI_WAYLAND_EVENTS_WAYLAND_EVENT_H_