chrome/browser/chromeos/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/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.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::keyboard_settings::ForceKeyboardDrivenUINavigation();
  25   }
  26
  27   return false;
  28 }
  29
  30 }  // namespace
  31
  32 KeyboardDrivenEventRewriter::KeyboardDrivenEventRewriter() {}
  33
  34 KeyboardDrivenEventRewriter::~KeyboardDrivenEventRewriter() {}
  35
  36 bool KeyboardDrivenEventRewriter::RewriteIfKeyboardDrivenOnLoginScreen(
  37     ui::KeyEvent* event) {
  38   if (!ShouldStripModifiersForArrowKeysAndEnter())
  39     return false;
  40
  41   return RewriteEvent(event);
  42 }
  43
  44 bool KeyboardDrivenEventRewriter::RewriteForTesting(ui::KeyEvent* event) {
  45   return RewriteEvent(event);
  46 }
  47
  48 bool KeyboardDrivenEventRewriter::RewriteEvent(ui::KeyEvent* event) {
  49   if ((event->flags() & kModifierMask) != kModifierMask)
  50     return false;
  51
  52   if (event->key_code() != ui::VKEY_LEFT &&
  53       event->key_code() != ui::VKEY_RIGHT &&
  54       event->key_code() != ui::VKEY_UP &&
  55       event->key_code() != ui::VKEY_DOWN &&
  56       event->key_code() != ui::VKEY_RETURN &&
  57       event->key_code() != ui::VKEY_F6) {
  58     return false;
  59   }
  60
  61   XEvent* xev = event->native_event();
  62   XKeyEvent* xkey = &(xev->xkey);
  63   xkey->state &= ~(ControlMask | Mod1Mask | ShiftMask);
  64   event->set_flags(event->flags() & ~kModifierMask);
  65   event->NormalizeFlags();
  66   return true;
  67 }
  68
  69 }  // namespace chromeos