chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc

   1 // Copyright (c) 2011 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/xinput_hierarchy_changed_event_listener.h"
   6
   7 #include <X11/Xlib.h>
   8 #include <X11/extensions/XInput2.h>
   9
  10 #include "chrome/browser/chromeos/input_method/input_method_manager.h"
  11 #include "chrome/browser/chromeos/input_method/xkeyboard.h"
  12 #include "ui/base/x/x11_util.h"
  13
  14 namespace {
  15
  16 // Gets the major opcode for XInput2. Returns -1 on error.
  17 int GetXInputOpCode() {
  18   static const char kExtensionName[] = "XInputExtension";
  19   int xi_opcode = -1;
  20   int event;
  21   int error;
  22
  23   if (!XQueryExtension(
  24           ui::GetXDisplay(), kExtensionName, &xi_opcode, &event, &error)) {
  25     VLOG(1) << "X Input extension not available: error=" << error;
  26     return -1;
  27   }
  28   return xi_opcode;
  29 }
  30
  31 // Starts listening to the XI_HierarchyChanged events.
  32 void SelectXInputEvents() {
  33   XIEventMask evmask;
  34   unsigned char mask[XIMaskLen(XI_LASTEVENT)] = {};
  35   XISetMask(mask, XI_HierarchyChanged);
  36
  37   evmask.deviceid = XIAllDevices;
  38   evmask.mask_len = sizeof(mask);
  39   evmask.mask = mask;
  40
  41   Display* display = ui::GetXDisplay();
  42   XISelectEvents(display, DefaultRootWindow(display), &evmask, 1);
  43 }
  44
  45 // Checks the |event| and asynchronously sets the XKB layout when necessary.
  46 void HandleHierarchyChangedEvent(XIHierarchyEvent* event) {
  47   if (!(event->flags & XISlaveAdded))
  48     return;
  49
  50   for (int i = 0; i < event->num_info; ++i) {
  51     XIHierarchyInfo* info = &event->info[i];
  52     if ((info->flags & XISlaveAdded) && (info->use == XIFloatingSlave)) {
  53       chromeos::input_method::InputMethodManager* input_method_manager =
  54           chromeos::input_method::InputMethodManager::GetInstance();
  55       chromeos::input_method::XKeyboard* xkeyboard =
  56           input_method_manager->GetXKeyboard();
  57       xkeyboard->ReapplyCurrentModifierLockStatus();
  58       xkeyboard->ReapplyCurrentKeyboardLayout();
  59       break;
  60     }
  61   }
  62 }
  63
  64 }  // namespace
  65
  66 namespace chromeos {
  67
  68 // static
  69 XInputHierarchyChangedEventListener*
  70 XInputHierarchyChangedEventListener::GetInstance() {
  71   return Singleton<XInputHierarchyChangedEventListener>::get();
  72 }
  73
  74 XInputHierarchyChangedEventListener::XInputHierarchyChangedEventListener()
  75     : stopped_(false),
  76       xiopcode_(GetXInputOpCode()) {
  77   SelectXInputEvents();
  78   Init();
  79 }
  80
  81 XInputHierarchyChangedEventListener::~XInputHierarchyChangedEventListener() {
  82   Stop();
  83 }
  84
  85 void XInputHierarchyChangedEventListener::Stop() {
  86   if (stopped_)
  87     return;
  88
  89   StopImpl();
  90   stopped_ = true;
  91   xiopcode_ = -1;
  92 }
  93
  94 void XInputHierarchyChangedEventListener::AddObserver(
  95     DeviceHierarchyObserver* observer) {
  96   observer_list_.AddObserver(observer);
  97 }
  98
  99 void XInputHierarchyChangedEventListener::RemoveObserver(
 100     DeviceHierarchyObserver* observer) {
 101   observer_list_.RemoveObserver(observer);
 102 }
 103
 104 bool XInputHierarchyChangedEventListener::ProcessedXEvent(XEvent* xevent) {
 105   if ((xevent->xcookie.type != GenericEvent) ||
 106       (xevent->xcookie.extension != xiopcode_)) {
 107     return false;
 108   }
 109
 110   XGenericEventCookie* cookie = &(xevent->xcookie);
 111   const bool hierarchy_changed = (cookie->evtype == XI_HierarchyChanged);
 112
 113   if (hierarchy_changed) {
 114     XIHierarchyEvent* event = static_cast<XIHierarchyEvent*>(cookie->data);
 115     HandleHierarchyChangedEvent(event);
 116     if (event->flags & XIDeviceEnabled || event->flags & XIDeviceDisabled)
 117       NotifyDeviceHierarchyChanged();
 118   }
 119
 120   return hierarchy_changed;
 121 }
 122
 123 void XInputHierarchyChangedEventListener::NotifyDeviceHierarchyChanged() {
 124   FOR_EACH_OBSERVER(DeviceHierarchyObserver,
 125                     observer_list_,
 126                     DeviceHierarchyChanged());
 127 }
 128
 129 }  // namespace chromeos