chrome/browser/chromeos/events/keyboard_driven_event_rewriter.cc

   1 // Copyright 2013 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 "chrome/browser/chromeos/events/keyboard_driven_event_rewriter.h"
   6
   7 #include <X11/Xlib.h>
   8
   9 #include "chrome/browser/chromeos/login/user_manager.h"
  10 #include "chrome/browser/chromeos/system/input_device_settings.h"
  11 #include "ui/events/event_utils.h"
  12
  13 namespace chromeos {
  14
  15 namespace {
  16
  17 const int kModifierMask = ui::EF_SHIFT_DOWN;
  18
  19 // Returns true if and only if it is on login screen (i.e. user is not logged
  20 // in) and the keyboard driven flag in the OEM manifest is on.
  21 bool ShouldStripModifiersForArrowKeysAndEnter() {
  22   if (UserManager::IsInitialized() &&
  23       !UserManager::Get()->IsUserLoggedIn()) {
  24     return system::InputDeviceSettings::Get()
  25         ->ForceKeyboardDrivenUINavigation();
  26   }
  27
  28   return false;
  29 }
  30
  31 }  // namespace
  32
  33 KeyboardDrivenEventRewriter::KeyboardDrivenEventRewriter() {}
  34
  35 KeyboardDrivenEventRewriter::~KeyboardDrivenEventRewriter() {}
  36
  37 bool KeyboardDrivenEventRewriter::RewriteIfKeyboardDrivenOnLoginScreen(
  38     XEvent* event) {
  39   if (!ShouldStripModifiersForArrowKeysAndEnter())
  40     return false;
  41
  42   return RewriteEvent(event);
  43 }
  44
  45 bool KeyboardDrivenEventRewriter::RewriteForTesting(XEvent* event) {
  46   return RewriteEvent(event);
  47 }
  48
  49 bool KeyboardDrivenEventRewriter::RewriteEvent(XEvent* event) {
  50   int flags = ui::EventFlagsFromNative(event);
  51   if ((flags & kModifierMask) != kModifierMask)
  52     return false;
  53   ui::KeyboardCode key_code = ui::KeyboardCodeFromNative(event);
  54
  55   if (key_code != ui::VKEY_LEFT &&
  56       key_code != ui::VKEY_RIGHT &&
  57       key_code != ui::VKEY_UP &&
  58       key_code != ui::VKEY_DOWN &&
  59       key_code != ui::VKEY_RETURN &&
  60       key_code != ui::VKEY_F6) {
  61     return false;
  62   }
  63
  64   XKeyEvent* xkey = &(event->xkey);
  65   xkey->state &= ~(ControlMask | Mod1Mask | ShiftMask);
  66   return true;
  67 }
  68
  69 }  // namespace chromeos