XKB implementation of Ozone key layout.

ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.cc

Index: ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.cc
diff --git a/ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.cc b/ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9090c442c6be7320de80cee28d2a81bb5b5e7c24
--- /dev/null
+++ b/ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.cc
@@ -0,0 +1,357 @@
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.h"
+
+#include <xkbcommon/xkbcommon-names.h>
+
+#include "base/logging.h"
+#include "ui/events/event_constants.h"
+#include "ui/events/keycodes/dom3/dom_key.h"
+#include "ui/events/keycodes/dom4/keycode_converter.h"
+#include "ui/events/ozone/layout/layout_util.h"
+#include "ui/events/ozone/layout/xkb/xkb_keyboard_code_conversion.h"
+
+namespace ui {
+
+namespace {
+
+// Temporarily hard-code an initial layout to test libxkbcommon.
+// TODO: remove this after SetCurrentLayoutByName() is implemented.
+const char* temporary_initial_keymap =
+    "xkb_keymap{"
+    "xkb_keycodes \"evdev_aliases(qwerty)\"{minimum=8;maximum=255;"
+    "<ESC>=9;<AE01>=10;<AE02>=11;<AE03>=12;<AE04>=13;<AE05>=14;"
+    "<AE06>=15;<AE07>=16;<AE08>=17;<AE09>=18;<AE10>=19;<AE11>=20;"
+    "<AE12>=21;<BKSP>=22;<TAB>=23;<AD01>=24;<AD02>=25;<AD03>=26;"
+    "<AD04>=27;<AD05>=28;<AD06>=29;<AD07>=30;<AD08>=31;<AD09>=32;"
+    "<AD10>=33;<AD11>=34;<AD12>=35;<RTRN>=36;<LCTL>=37;<AC01>=38;"
+    "<AC02>=39;<AC03>=40;<AC04>=41;<AC05>=42;<AC06>=43;<AC07>=44;"
+    "<AC08>=45;<AC09>=46;<AC10>=47;<AC11>=48;<TLDE>=49;<LFSH>=50;"
+    "<BKSL>=51;<AB01>=52;<AB02>=53;<AB03>=54;<AB04>=55;<AB05>=56;"
+    "<AB06>=57;<AB07>=58;<AB08>=59;<AB09>=60;<AB10>=61;<RTSH>=62;"
+    "<KPMU>=63;<LALT>=64;<SPCE>=65;<CAPS>=66;<FK01>=67;<FK02>=68;"
+    "<FK03>=69;<FK04>=70;<FK05>=71;<FK06>=72;<FK07>=73;<FK08>=74;"
+    "<FK09>=75;<FK10>=76;<FK11>=95;<FK12>=96;<FK13>=191;<FK14>=192;"
+    "<FK15>=193;<FK16>=194;<FK17>=195;<FK18>=196;<FK19>=197;<FK20>=198;"
+    "<FK21>=199;<FK22>=200;<FK23>=201;<FK24>=202;<LWIN>=133;<RWIN>=134;"
+    "<NMLK>=77;<SCLK>=78;<KP7>=79;<KP8>=80;<KP9>=81;<KPSU>=82;<KP4>=83;"
+    "<KP5>=84;<KP6>=85;<KPAD>=86;<KP1>=87;<KP2>=88;<KP3>=89;<KP0>=90;"
+    "<KPDL>=91;<LVL3>=92;<LSGT>=94;<FK11>=95;<FK12>=96;<KATA>=98;<HIRA>=99;"
+    "<HENK>=100;<HKTG>=101;<MUHE>=102;<KPEN>=104;<RCTL>=105;"
+    "<KPDV>=106;<PRSC>=107;<RALT>=108;<LNFD>=109;<HOME>=110;<UP>=111;"
+    "<PGUP>=112;<LEFT>=113;<RGHT>=114;<END>=115;<DOWN>=116;<PGDN>=117;"
+    "<INS>=118;<DELE>=119;<MUTE>=121;<VOL->=122;<VOL+>=123;<POWR>=124;"
+    "<MDSW>=203;<ALT>=204;<META>=205;<SUPR>=206;<HYPR>=207;};"
+    "xkb_types \"complete\"{virtual_modifiers NumLock,Alt,LevelThree,LAlt,"
+    "RAlt,RControl,LControl,ScrollLock,LevelFive,AltGr,Meta,Super,Hyper;"
+    "type \"ONE_LEVEL\"{modifiers=none;level_name[Level1]=\"Any\";};"
+    "type \"TWO_LEVEL\"{modifiers=Shift;map[Shift]=Level2;"
+    "level_name[Level1]=\"Base\";level_name[Level2]=\"Shift\";};"
+    "type \"ALPHABETIC\"{modifiers=Shift+Lock;"
+    "map[Shift]=Level2;map[Lock]=Level2;"
+    "level_name[Level1]=\"Base\";level_name[Level2]=\"Caps\";};"
+    "type \"FOUR_LEVEL\"{modifiers=Shift+LevelThree;map[Shift]=Level2;"
+    "map[LevelThree]=Level3;map[Shift+LevelThree]=Level4;"
+    "level_name[Level1]=\"Base\";level_name[Level2]=\"Shift\";"
+    "level_name[Level3]=\"Alt Base\";level_name[Level4]=\"Shift Alt\";};"
+    "type \"KEYPAD\"{modifiers=Shift+NumLock;"
+    "map[Shift]=Level2;map[NumLock]=Level2;"
+    "level_name[Level1]=\"Base\";level_name[Level2]=\"Number\";};};"
+    "xkb_compatibility \"complete\"{virtual_modifiers NumLock,Alt,LevelThree,"
+    "LAlt,RAlt,RControl,LControl,ScrollLock,LevelFive,AltGr,Meta,Super,Hyper;"
+    "interpret.useModMapMods=AnyLevel;interpret.repeat=False;"
+    "interpret ISO_Level2_Latch+Exactly(Shift){useModMapMods=level1;"
+    "action=LatchMods(modifiers=Shift,clearLocks,latchToLock);};"
+    "interpret Shift_Lock+AnyOf(Shift+Lock){action=LockMods(modifiers=Shift);};"
+    "interpret Num_Lock+AnyOf(all){virtualModifier=NumLock;"
+    "action=LockMods(modifiers=NumLock);};"
+    "interpret ISO_Level3_Shift+AnyOf(all){virtualModifier=LevelThree;"
+    "useModMapMods=level1;action=SetMods(modifiers=LevelThree,clearLocks);};"
+    "interpret ISO_Level3_Latch+AnyOf(all){"
+    "virtualModifier=LevelThree;useModMapMods=level1;"
+    "action=LatchMods(modifiers=LevelThree,clearLocks,latchToLock);};"
+    "interpret ISO_Level3_Lock+AnyOf(all){virtualModifier=LevelThree;"
+    "useModMapMods=level1;action=LockMods(modifiers=LevelThree);};"
+    "interpret Alt_L+AnyOf(all){virtualModifier=Alt;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Alt_R+AnyOf(all){virtualModifier=Alt;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Meta_L+AnyOf(all){virtualModifier=Meta;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Meta_R+AnyOf(all){virtualModifier=Meta;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Super_L+AnyOf(all){virtualModifier=Super;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Super_R+AnyOf(all){virtualModifier=Super;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Hyper_L+AnyOf(all){virtualModifier=Hyper;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Hyper_R+AnyOf(all){virtualModifier=Hyper;"
+    "action=SetMods(modifiers=modMapMods,clearLocks);};"
+    "interpret Mode_switch+AnyOfOrNone(all){virtualModifier=AltGr;"
+    "useModMapMods=level1;action=SetGroup(group=+1);};"
+    "interpret ISO_Level3_Shift+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=LevelThree,clearLocks);};"
+    "interpret ISO_Level3_Latch+AnyOfOrNone(all){"
+    "action=LatchMods(modifiers=LevelThree,clearLocks,latchToLock);};"
+    "interpret ISO_Level3_Lock+AnyOfOrNone(all){"
+    "action=LockMods(modifiers=LevelThree);};"
+    "interpret Alt_L+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Alt,clearLocks);};"
+    "interpret Alt_R+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Alt,clearLocks);};"
+    "interpret Meta_L+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Meta,clearLocks);};"
+    "interpret Meta_R+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Meta,clearLocks);};"
+    "interpret Super_L+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Super,clearLocks);};"
+    "interpret Super_R+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Super,clearLocks);};"
+    "interpret Hyper_L+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Hyper,clearLocks);};"
+    "interpret Hyper_R+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Hyper,clearLocks);};"
+    "interpret Shift_L+AnyOfOrNone(all){"
+    "action=SetMods(modifiers=Shift,clearLocks);};"
+    "interpret XF86Switch_VT_1+AnyOfOrNone(all){repeat=True;"
+    "action=SwitchScreen(screen=1,!same);};"
+    "interpret XF86Switch_VT_2+AnyOfOrNone(all){repeat=True;"
+    "action=SwitchScreen(screen=2,!same);};"
+    "interpret XF86Switch_VT_3+AnyOfOrNone(all){repeat=True;"
+    "action=SwitchScreen(screen=3,!same);};"
+    "interpret XF86Switch_VT_4+AnyOfOrNone(all){repeat=True;"
+    "action=SwitchScreen(screen=4,!same);};"
+    "interpret Caps_Lock+AnyOfOrNone(all){action=LockMods(modifiers=Lock);};"
+    "interpret Any+Exactly(Lock){action=LockMods(modifiers=Lock);};"
+    "interpret Any+AnyOf(all){action=SetMods(modifiers=modMapMods,clearLocks);"
+    "};};"
+    "xkb_symbols \"pc_us_inet(evdev)\"{name[group1]=\"English (US)\";"
+    "key<ESC>{[Escape]};key<AE01>{[1,exclam]};key<AE02>{[2,at]};"
+    "key<AE03>{[3,numbersign]};key<AE04>{[4,dollar]};key<AE05>{[5,percent]};"
+    "key<AE06>{[6,asciicircum]};key<AE07>{[7,ampersand]};"
+    "key<AE08>{[8,asterisk]};key<AE09>{[9,parenleft]};"
+    "key<AE10>{[0,parenright]};key<AE11>{[minus,underscore]};"
+    "key<AE12>{[equal,plus]};key<BKSP>{[BackSpace,BackSpace]};"
+    "key<TAB>{[Tab,ISO_Left_Tab]};key<AD01>{[q,Q]};key<AD02>{[w,W]};"
+    "key<AD03>{[e,E]};key<AD04>{[r,R]};key<AD05>{[t,T]};key<AD06>{[y,Y]};"
+    "key<AD07>{[u,U]};key<AD08>{[i,I]};key<AD09>{[o,O]};key<AD10>{[p,P]};"
+    "key<AD11>{[bracketleft,braceleft]};key<AD12>{[bracketright,braceright]};"
+    "key<RTRN>{[Return]};key<LCTL>{[Control_L]};key<AC01>{[a,A]};"
+    "key<AC02>{[s,S]};key<AC03>{[d,D]};key<AC04>{[f,F]};key<AC05>{[g,G]};"
+    "key<AC06>{[h,H]};key<AC07>{[j,J]};key<AC08>{[k,K]};key<AC09>{[l,L]};"
+    "key<AC10>{[semicolon,colon]};key<AC11>{[apostrophe,quotedbl]};"
+    "key<TLDE>{[grave,asciitilde]};key<LFSH>{[Shift_L]};"
+    "key<BKSL>{[backslash,bar]};key<AB01>{[z,Z]};key<AB02>{[x,X]};"
+    "key<AB03>{[c,C]};key<AB04>{[v,V]};key<AB05>{[b,B]};key<AB06>{[n,N]};"
+    "key<AB07>{[m,M]};key<AB08>{[comma,less]};key<AB09>{[period,greater]};"
+    "key<AB10>{[slash,question]};key<RTSH>{[Shift_R]};"
+    "key<KPMU>{[KP_Multiply,KP_Multiply]};key<LALT>{[Alt_L,Meta_L]};"
+    "key<SPCE>{[space]};key<CAPS>{[Caps_Lock]};key<FK01>{[F1,F1]};"
+    "key<FK02>{[F2,F2]};key<FK03>{[F3,F3]};key<FK04>{[F4,F4]};"
+    "key<FK05>{[F5,F5]};key<FK06>{[F6,F6]};key<FK07>{[F7,F7]};"
+    "key<FK08>{[F8,F8]};key<FK09>{[F9,F9]};key<FK10>{[F10,F10]};"
+    "key<FK11>{[F11,F11]};key<FK12>{[F12,F12]};key<FK13>{[F13,F13]};"
+    "key<FK14>{[F14,F14]};key<FK15>{[F15,F15]};key<FK16>{[F16,F16]};"
+    "key<FK17>{[F17,F17]};key<FK18>{[F18,F18]};key<FK19>{[F19,F19]};"
+    "key<FK20>{[F20,F20]};key<FK21>{[F21,F21]};key<FK22>{[F22,F22]};"
+    "key<FK23>{[F23,F23]}; key<FK24>{[F24,F24]};"
+    "key<NMLK>{[Num_Lock]};key<SCLK>{[Scroll_Lock]};"
+    "key<KP7>{[KP_Home,KP_7]};key<KP8>{[KP_Up,KP_8]};key<KP9>{[KP_Prior,KP_9]};"
+    "key<KPSU>{[KP_Subtract,KP_Subtract]};key<KP4>{[KP_Left,KP_4]};"
+    "key<KP5>{[KP_Begin,KP_5]};key<KP6>{[KP_Right,KP_6]};"
+    "key<KPAD>{[KP_Add,KP_Add]};key<KP1>{[KP_End,KP_1]};"
+    "key<KP2>{[KP_Down,KP_2]};key<KP3>{[KP_Next,KP_3]};"
+    "key<KP0>{[KP_Insert,KP_0]};key<KPDL>{[KP_Delete,KP_Decimal]};"
+    "key<LVL3>{[ISO_Level3_Shift]};key<LSGT>{[less,greater, bar,brokenbar]};"
+    "key<FK11>{[F11,F11]};key<FK12>{[F12,F12]};key<KATA>{[Katakana]};"
+    "key<HIRA>{[Hiragana]};key<HENK>{[Henkan_Mode]};"
+    "key<HKTG>{[Hiragana_Katakana]};key<MUHE>{[Muhenkan]};"
+    "key<KPEN>{[KP_Enter]};key<RCTL>{[Control_R]};key<MDSW>{[Mode_switch]};"
+    "key<KPDV>{[KP_Divide,KP_Divide]};key<PRSC>{[Print,Sys_Req]};"
+    "key<RALT>{type=\"TWO_LEVEL\",symbols[Group1]=[Alt_R,Meta_R]};"
+    "key<LNFD>{[Linefeed]};key<HOME>{[Home]};key<UP>{[Up]};key<PGUP>{[Prior]};"
+    "key<LEFT>{[Left]};key<RGHT>{[Right]};key<END>{[End]};key<DOWN>{[Down]};"
+    "key<PGDN>{[Next]};key<INS>{[Insert]};key<DELE>{[Delete]};"
+    "key<MUTE>{[XF86AudioMute]};key<VOL->{[XF86AudioLowerVolume]};"
+    "key<VOL+>{[XF86AudioRaiseVolume]};key<POWR>{[XF86PowerOff]};"
+    "key<ALT>{[NoSymbol,Alt_L]};key<META>{[NoSymbol,Meta_L]};"
+    "key<SUPR>{[NoSymbol,Super_L]};key<HYPR>{[NoSymbol,Hyper_L]};"
+    "key<LWIN>{[Super_L,Super_L]};key<RWIN>{[Super_R,Super_R]};"
+    "modifier_map Control{<LCTL>};modifier_map Shift{<LFSH>};"
+    "modifier_map Shift{<RTSH>};modifier_map Mod1{<LALT>};"
+    "modifier_map Lock{<CAPS>};modifier_map Mod2{<NMLK>};"
+    "modifier_map Mod5{<LVL3>};modifier_map Control{<RCTL>};"
+    "modifier_map Mod1{<RALT>};modifier_map Mod5{<MDSW>};"
+    "modifier_map Mod1{<META>};modifier_map Mod4{<SUPR>};"
+    "modifier_map Mod4{<LWIN>};modifier_map Mod4{<RWIN>};"
+    "modifier_map Mod4{<HYPR>};};};";
+
+DomKey CharacterToDomKey(base::char16 character) {
+  switch (character) {
+    case 0x08:
+      return DomKey::BACKSPACE;
+    case 0x09:
+      return DomKey::TAB;
+    case 0x0A:
+    case 0x0D:
+      return DomKey::ENTER;
+    case 0x1B:
+      return DomKey::ESCAPE;
+    default:
+      return DomKey::CHARACTER;
+  }
+}
+
+KeyboardCode DifficultKeyboardCode(DomCode dom_code,
+                                   int flags,
+                                   DomKey dom_key,
+                                   base::char16 character) {
+  // TODO(kpschoedel): correct key_code for non-US layouts along the lines
+  // of KeyboardCodeFromXKeyEvent()
+  return DomCodeToKeyboardCode(dom_code);
+}
+
+}  // anonymous namespace
+
+XkbKeyCodeConverter::XkbKeyCodeConverter() {
+}
+
+XkbKeyCodeConverter::~XkbKeyCodeConverter() {
+}
+
+XkbKeyboardLayoutEngine::XkbKeyboardLayoutEngine(
+    const XkbKeyCodeConverter& converter)
+    : key_code_converter_(converter) {
+  // TODO: add XKB_CONTEXT_NO_ENVIRONMENT_NAMES
+  xkb_context_.reset(xkb_context_new(XKB_CONTEXT_NO_DEFAULT_INCLUDES));
+
+  // Temporary initial keymap to avoid file I/O on initialization.
+  // TODO: remove this after SetCurrentLayoutByName() is implemented.
+  xkb_keymap* keymap = xkb_keymap_new_from_string(
+      xkb_context_.get(), temporary_initial_keymap, XKB_KEYMAP_FORMAT_TEXT_V1,
+      XKB_KEYMAP_COMPILE_NO_FLAGS);
+  SetKeymap(keymap);
+}
+
+XkbKeyboardLayoutEngine::~XkbKeyboardLayoutEngine() {
+}
+
+bool XkbKeyboardLayoutEngine::CanSetCurrentLayout() const {
+#if defined(OS_CHROMEOS)
+  return true;
+#else
+  return false;
+#endif
+}
+
+bool XkbKeyboardLayoutEngine::SetCurrentLayoutByName(
+    const std::string& layout_name) {
+#if defined(OS_CHROMEOS)
+  // TODO(fengyuan)
+  // End successful set with SetKeymap(keymap) to update other fields.
+  return false;
+#else
+  return false;
+#endif
+}
+
+bool XkbKeyboardLayoutEngine::UsesISOLevel5Shift() const {
+  // NOTIMPLEMENTED();
+  return false;
+}
+
+bool XkbKeyboardLayoutEngine::UsesAltGr() const {
+  // NOTIMPLEMENTED();
+  return false;
+}
+
+bool XkbKeyboardLayoutEngine::Lookup(DomCode dom_code,
+                                     int flags,
+                                     DomKey* dom_key,
+                                     base::char16* character,
+                                     KeyboardCode* key_code) const {
+  xkb_keycode_t xkb_keycode = key_code_converter_.DomCodeToXkbKeyCode(dom_code);
+  if (xkb_keycode == key_code_converter_.InvalidXkbKeyCode()) {
+    LOG(ERROR) << "No XKB keycode for DomCode 0x" << std::hex
+               << static_cast<int>(dom_code) << " '"
+               << KeycodeConverter::DomCodeToCodeString(dom_code) << "'";
+    return false;
+  }
+  xkb_mod_mask_t xkb_flags = EventFlagsToXkbFlags(flags);
+  xkb_keysym_t xkb_keysym;
+  if (!XkbLookup(xkb_keycode, xkb_flags, &xkb_keysym, character))
+    return false;
+  *dom_key = XkbKeySymToDomKey(xkb_keysym);
+  if (*dom_key == DomKey::NONE) {
+    *dom_key = CharacterToDomKey(*character);
+    *key_code = DifficultKeyboardCode(dom_code, flags, *dom_key, *character);
+  } else if (*dom_key == DomKey::DEAD) {
+    *character = XkbKeySymDeadKey(xkb_keysym);
+    *key_code = DomCodeToKeyboardCode(dom_code);
+  } else {
+    *key_code = NonPrintableDomKeyToKeyboardCode(*dom_key);
+    if (*key_code == VKEY_UNKNOWN)
+      *key_code = DomCodeToKeyboardCode(dom_code);
+  }
+  return true;
+}
+
+void XkbKeyboardLayoutEngine::SetKeymap(xkb_keymap* keymap) {
+  xkb_state_.reset(xkb_state_new(keymap));
+  // Update flag map.
+  static struct {

[spang, 2014/12/08 22:47:29]

const

[kpschoedel, 2014/12/15 19:48:46]

Done.

+    int ui_flag;
+    const char* xkb_name;
+  } flags[] = {{ui::EF_CONTROL_DOWN, XKB_MOD_NAME_CTRL},
+               {ui::EF_SHIFT_DOWN, XKB_MOD_NAME_SHIFT},
+               {ui::EF_ALT_DOWN, XKB_MOD_NAME_ALT},
+               {ui::EF_CAPS_LOCK_DOWN, XKB_MOD_NAME_CAPS},
+               {ui::EF_COMMAND_DOWN, XKB_MOD_NAME_LOGO},
+               {ui::EF_NUMPAD_KEY, XKB_MOD_NAME_NUM},
+               {ui::EF_MOD3_DOWN, "Mod3"},
+               {ui::EF_ALTGR_DOWN, "Mod5"}};
+  xkb_flag_map_.clear();
+  xkb_flag_map_.resize(arraysize(flags));
+  for (size_t i = 0; i < arraysize(flags); ++i) {
+    xkb_mod_index_t index = xkb_keymap_mod_get_index(keymap, flags[i].xkb_name);
+    if (index == XKB_MOD_INVALID) {
+      DVLOG(3) << "XKB keyboard layout does not contain " << flags[i].xkb_name;
+    } else {
+      xkb_mod_mask_t flag = static_cast<xkb_mod_mask_t>(1) << index;
+      XkbFlagMapEntry e = {flags[i].ui_flag, flag};
+      xkb_flag_map_.push_back(e);
+    }
+  }
+}
+
+xkb_mod_mask_t XkbKeyboardLayoutEngine::EventFlagsToXkbFlags(
+    int ui_flags) const {
+  xkb_mod_mask_t xkb_flags = 0;
+  for (const auto& entry : xkb_flag_map_) {
+    if (ui_flags & entry.ui_flag)
+      xkb_flags |= entry.xkb_flag;
+  }
+  return xkb_flags;
+}
+
+bool XkbKeyboardLayoutEngine::XkbLookup(xkb_keycode_t xkb_keycode,
+                                        xkb_mod_mask_t xkb_flags,
+                                        xkb_keysym_t* xkb_keysym,
+                                        base::char16* character) const {
+  if (!xkb_state_) {
+    LOG(ERROR) << "No current XKB state";
+    return false;
+  }
+  xkb_state_update_mask(xkb_state_.get(), xkb_flags, 0, 0, 0, 0, 0);
+  *xkb_keysym = xkb_state_key_get_one_sym(xkb_state_.get(), xkb_keycode);
+  if (*xkb_keysym == XKB_KEY_NoSymbol)
+    return false;
+  uint32_t c = xkb_state_key_get_utf32(xkb_state_.get(), xkb_keycode);
+  DLOG_IF(ERROR, c != (c & 0xFFFF)) << "Non-BMP character:" << c;
+  *character = static_cast<base::char16>(c);
+  return true;
+}
+
+}  // namespace ui