ozone: evdev: Handle mouse events

ui/events/ozone/evdev/event_converter_evdev_impl.cc

+// 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.
+
+#include "ui/events/ozone/evdev/event_converter_evdev_impl.h"
+
+#include <errno.h>
+#include <linux/input.h>
+
+#include "base/message_loop/message_loop.h"
+#include "ui/events/event.h"
+#include "ui/events/keycodes/dom4/keycode_converter.h"
+#include "ui/events/keycodes/keyboard_codes.h"
+
+namespace ui {
+
+EventConverterEvdevImpl::EventConverterEvdevImpl(
+    int fd,
+    base::FilePath path,
+    int id,
+    EventModifiersEvdev* modifiers,
+    CursorDelegateEvdev* cursor,
+    KeyboardEvdev* keyboard,
+    const EventDispatchCallback& callback)
+    : EventConverterEvdev(fd, path, id),
+      x_offset_(0),
+      y_offset_(0),
+      cursor_(cursor),
+      keyboard_(keyboard),
+      modifiers_(modifiers),
+      callback_(callback) {
+}
+
+EventConverterEvdevImpl::~EventConverterEvdevImpl() {
+  Stop();
+  close(fd_);
+}
+
+void EventConverterEvdevImpl::OnFileCanReadWithoutBlocking(int fd) {
+  input_event inputs[4];
+  ssize_t read_size = read(fd, inputs, sizeof(inputs));
+  if (read_size < 0) {
+    if (errno == EINTR || errno == EAGAIN)
+      return;
+    if (errno != ENODEV)
+      PLOG(ERROR) << "error reading device " << path_.value();
+    Stop();
+    return;
+  }
+
+  DCHECK_EQ(read_size % sizeof(*inputs), 0u);
+  ProcessEvents(inputs, read_size / sizeof(*inputs));
+}
+
+void EventConverterEvdevImpl::ProcessEvents(const input_event* inputs,
+                                           int count) {
+  for (int i = 0; i < count; ++i) {
+    const input_event& input = inputs[i];
+    switch (input.type) {
+      case EV_KEY:
+        ConvertKeyEvent(input);
+        break;
+      case EV_REL:
+        ConvertMouseMoveEvent(input);
+        break;
+      case EV_SYN:
+        FlushEvents();
+        break;
+    }
+  }
+}
+
+void EventConverterEvdevImpl::ConvertKeyEvent(const input_event& input) {
+  // Mouse processing.
+  if (input.code >= BTN_MOUSE && input.code < BTN_JOYSTICK) {
+    DispatchMouseButton(input);
+    return;
+  }
+  // Keyboard processing.
+  keyboard_->OnKeyChange(input.code, input.value != 0);
+}
+
+void EventConverterEvdevImpl::ConvertMouseMoveEvent(const input_event& input) {
+  if (!cursor_)
+    return;
+  switch (input.code) {
+    case REL_X:
+      x_offset_ = input.value;
+      break;
+    case REL_Y:
+      y_offset_ = input.value;
+      break;
+  }
+}
+
+void EventConverterEvdevImpl::DispatchMouseButton(const input_event& input) {
+  if (!cursor_)
+    return;
+
+  unsigned int modifier;
+  if (input.code == BTN_LEFT)
+    modifier = EVDEV_MODIFIER_LEFT_MOUSE_BUTTON;
+  else if (input.code == BTN_RIGHT)
+    modifier = EVDEV_MODIFIER_RIGHT_MOUSE_BUTTON;
+  else if (input.code == BTN_MIDDLE)
+    modifier = EVDEV_MODIFIER_MIDDLE_MOUSE_BUTTON;
+  else
+    return;
+
+  int flag = modifiers_->GetEventFlagFromModifier(modifier);
+  modifiers_->UpdateModifier(modifier, input.value);
+  callback_.Run(make_scoped_ptr(
+      new MouseEvent(input.value ? ET_MOUSE_PRESSED : ET_MOUSE_RELEASED,
+                     cursor_->location(),
+                     cursor_->location(),
+                     modifiers_->GetModifierFlags() | flag,
+                     flag)));
+}
+
+void EventConverterEvdevImpl::FlushEvents() {
+  if (!cursor_ || (x_offset_ == 0 && y_offset_ == 0))
+    return;
+
+  cursor_->MoveCursor(gfx::Vector2dF(x_offset_, y_offset_));
+
+  callback_.Run(make_scoped_ptr(
+      new MouseEvent(ui::ET_MOUSE_MOVED,
+                     cursor_->location(),
+                     cursor_->location(),
+                     modifiers_->GetModifierFlags(),
+                     /* changed_button_flags */ 0)));
+  x_offset_ = 0;
+  y_offset_ = 0;
+}
+
+}  // namespace ui