• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 "ui/base/ime/win/imm32_manager.h"
6 
7 #include <msctf.h>
8 
9 #include "base/basictypes.h"
10 #include "base/memory/scoped_ptr.h"
11 #include "base/strings/string16.h"
12 #include "base/strings/string_util.h"
13 #include "base/strings/utf_string_conversions.h"
14 #include "base/win/scoped_comptr.h"
15 #include "third_party/skia/include/core/SkColor.h"
16 #include "ui/base/ime/composition_text.h"
17 
18 // "imm32.lib" is required by IMM32 APIs used in this file.
19 // NOTE(hbono): To comply with a comment from Darin, I have added
20 // this #pragma directive instead of adding "imm32.lib" to a project file.
21 #pragma comment(lib, "imm32.lib")
22 
23 // Following code requires wchar_t to be same as char16. It should always be
24 // true on Windows.
25 COMPILE_ASSERT(sizeof(wchar_t) == sizeof(base::char16), wchar_t__char16_diff);
26 
27 ///////////////////////////////////////////////////////////////////////////////
28 // IMM32Manager
29 
30 namespace {
31 
32 // Determines whether or not the given attribute represents a target
33 // (a.k.a. a selection).
IsTargetAttribute(char attribute)34 bool IsTargetAttribute(char attribute) {
35   return (attribute == ATTR_TARGET_CONVERTED ||
36           attribute == ATTR_TARGET_NOTCONVERTED);
37 }
38 
39 // Helper function for IMM32Manager::GetCompositionInfo() method, to get the
40 // target range that's selected by the user in the current composition string.
GetCompositionTargetRange(HIMC imm_context,int * target_start,int * target_end)41 void GetCompositionTargetRange(HIMC imm_context, int* target_start,
42                                int* target_end) {
43   int attribute_size = ::ImmGetCompositionString(imm_context, GCS_COMPATTR,
44                                                  NULL, 0);
45   if (attribute_size > 0) {
46     int start = 0;
47     int end = 0;
48     scoped_ptr<char[]> attribute_data(new char[attribute_size]);
49     if (attribute_data.get()) {
50       ::ImmGetCompositionString(imm_context, GCS_COMPATTR,
51                                 attribute_data.get(), attribute_size);
52       for (start = 0; start < attribute_size; ++start) {
53         if (IsTargetAttribute(attribute_data[start]))
54           break;
55       }
56       for (end = start; end < attribute_size; ++end) {
57         if (!IsTargetAttribute(attribute_data[end]))
58           break;
59       }
60     }
61     *target_start = start;
62     *target_end = end;
63   }
64 }
65 
66 // Helper function for IMM32Manager::GetCompositionInfo() method, to get
67 // underlines information of the current composition string.
GetCompositionUnderlines(HIMC imm_context,int target_start,int target_end,ui::CompositionUnderlines * underlines)68 void GetCompositionUnderlines(HIMC imm_context,
69                               int target_start,
70                               int target_end,
71                               ui::CompositionUnderlines* underlines) {
72   int clause_size = ::ImmGetCompositionString(imm_context, GCS_COMPCLAUSE,
73                                               NULL, 0);
74   int clause_length = clause_size / sizeof(uint32);
75   if (clause_length) {
76     scoped_ptr<uint32[]> clause_data(new uint32[clause_length]);
77     if (clause_data.get()) {
78       ::ImmGetCompositionString(imm_context, GCS_COMPCLAUSE,
79                                 clause_data.get(), clause_size);
80       for (int i = 0; i < clause_length - 1; ++i) {
81         ui::CompositionUnderline underline;
82         underline.start_offset = clause_data[i];
83         underline.end_offset = clause_data[i+1];
84         underline.color = SK_ColorBLACK;
85         underline.thick = false;
86         underline.background_color = SK_ColorTRANSPARENT;
87 
88         // Use thick underline for the target clause.
89         if (underline.start_offset >= static_cast<uint32>(target_start) &&
90             underline.end_offset <= static_cast<uint32>(target_end)) {
91           underline.thick = true;
92         }
93         underlines->push_back(underline);
94       }
95     }
96   }
97 }
98 
99 // Checks if a given primary language ID is a RTL language.
IsRTLPrimaryLangID(LANGID lang)100 bool IsRTLPrimaryLangID(LANGID lang) {
101   switch (lang) {
102     case LANG_ARABIC:
103     case LANG_HEBREW:
104     case LANG_PERSIAN:
105     case LANG_SYRIAC:
106     case LANG_UIGHUR:
107     case LANG_URDU:
108       return true;
109     default:
110       return false;
111   }
112 }
113 
114 }  // namespace
115 
116 namespace ui {
117 
IMM32Manager()118 IMM32Manager::IMM32Manager()
119     : ime_status_(false),
120       input_language_id_(LANG_USER_DEFAULT),
121       is_composing_(false),
122       system_caret_(false),
123       caret_rect_(-1, -1, 0, 0),
124       use_composition_window_(false) {
125 }
126 
~IMM32Manager()127 IMM32Manager::~IMM32Manager() {
128 }
129 
SetInputLanguage()130 bool IMM32Manager::SetInputLanguage() {
131   // Retrieve the current keyboard layout from Windows and determine whether
132   // or not the current input context has IMEs.
133   // Also save its input language for language-specific operations required
134   // while composing a text.
135   HKL keyboard_layout = ::GetKeyboardLayout(0);
136   input_language_id_ = reinterpret_cast<LANGID>(keyboard_layout);
137 
138   // Check TSF Input Processor first.
139   // If the active profile is TSF INPUTPROCESSOR, this is IME.
140   base::win::ScopedComPtr<ITfInputProcessorProfileMgr> prof_mgr;
141   TF_INPUTPROCESSORPROFILE prof;
142   if (SUCCEEDED(prof_mgr.CreateInstance(CLSID_TF_InputProcessorProfiles)) &&
143       SUCCEEDED(prof_mgr->GetActiveProfile(GUID_TFCAT_TIP_KEYBOARD, &prof)) &&
144       prof.hkl == NULL &&
145       prof.dwProfileType == TF_PROFILETYPE_INPUTPROCESSOR) {
146       ime_status_ = true;
147   } else {
148     // If the curent language is not using TSF, check IMM32 based IMEs.
149     // As ImmIsIME always returns non-0 value on Vista+, use ImmGetIMEFileName
150     // instead to check if this HKL has any associated IME file.
151     ime_status_ = (ImmGetIMEFileName(keyboard_layout, NULL, 0) != 0);
152   }
153 
154   return ime_status_;
155 }
156 
CreateImeWindow(HWND window_handle)157 void IMM32Manager::CreateImeWindow(HWND window_handle) {
158   // When a user disables TSF (Text Service Framework) and CUAS (Cicero
159   // Unaware Application Support), Chinese IMEs somehow ignore function calls
160   // to ::ImmSetCandidateWindow(), i.e. they do not move their candidate
161   // window to the position given as its parameters, and use the position
162   // of the current system caret instead, i.e. it uses ::GetCaretPos() to
163   // retrieve the position of their IME candidate window.
164   // Therefore, we create a temporary system caret for Chinese IMEs and use
165   // it during this input context.
166   // Since some third-party Japanese IME also uses ::GetCaretPos() to determine
167   // their window position, we also create a caret for Japanese IMEs.
168   if (PRIMARYLANGID(input_language_id_) == LANG_CHINESE ||
169       PRIMARYLANGID(input_language_id_) == LANG_JAPANESE) {
170     if (!system_caret_) {
171       if (::CreateCaret(window_handle, NULL, 1, 1)) {
172         system_caret_ = true;
173       }
174     }
175   }
176   // Restore the positions of the IME windows.
177   UpdateImeWindow(window_handle);
178 }
179 
SetImeWindowStyle(HWND window_handle,UINT message,WPARAM wparam,LPARAM lparam,BOOL * handled)180 LRESULT IMM32Manager::SetImeWindowStyle(HWND window_handle, UINT message,
181                                     WPARAM wparam, LPARAM lparam,
182                                     BOOL* handled) {
183   // To prevent the IMM (Input Method Manager) from displaying the IME
184   // composition window, Update the styles of the IME windows and EXPLICITLY
185   // call ::DefWindowProc() here.
186   // NOTE(hbono): We can NEVER let WTL call ::DefWindowProc() when we update
187   // the styles of IME windows because the 'lparam' variable is a local one
188   // and all its updates disappear in returning from this function, i.e. WTL
189   // does not call ::DefWindowProc() with our updated 'lparam' value but call
190   // the function with its original value and over-writes our window styles.
191   *handled = TRUE;
192   lparam &= ~ISC_SHOWUICOMPOSITIONWINDOW;
193   return ::DefWindowProc(window_handle, message, wparam, lparam);
194 }
195 
DestroyImeWindow(HWND window_handle)196 void IMM32Manager::DestroyImeWindow(HWND window_handle) {
197   // Destroy the system caret if we have created for this IME input context.
198   if (system_caret_) {
199     ::DestroyCaret();
200     system_caret_ = false;
201   }
202 }
203 
MoveImeWindow(HWND window_handle,HIMC imm_context)204 void IMM32Manager::MoveImeWindow(HWND window_handle, HIMC imm_context) {
205   // Does nothing when the target window has no input focus. This is important
206   // because the renderer may issue SelectionBoundsChanged event even when it
207   // has no input focus. (e.g. the page update caused by incremental search.)
208   // So this event should be ignored when the |window_handle| no longer has the
209   // input focus.
210   if (GetFocus() != window_handle)
211     return;
212 
213   int x = caret_rect_.x();
214   int y = caret_rect_.y();
215 
216   const int kCaretMargin = 1;
217   if (!use_composition_window_ &&
218       PRIMARYLANGID(input_language_id_) == LANG_CHINESE) {
219     // As written in a comment in IMM32Manager::CreateImeWindow(),
220     // Chinese IMEs ignore function calls to ::ImmSetCandidateWindow()
221     // when a user disables TSF (Text Service Framework) and CUAS (Cicero
222     // Unaware Application Support).
223     // On the other hand, when a user enables TSF and CUAS, Chinese IMEs
224     // ignore the position of the current system caret and uses the
225     // parameters given to ::ImmSetCandidateWindow() with its 'dwStyle'
226     // parameter CFS_CANDIDATEPOS.
227     // Therefore, we do not only call ::ImmSetCandidateWindow() but also
228     // set the positions of the temporary system caret if it exists.
229     CANDIDATEFORM candidate_position = {0, CFS_CANDIDATEPOS, {x, y},
230                                         {0, 0, 0, 0}};
231     ::ImmSetCandidateWindow(imm_context, &candidate_position);
232   }
233   if (system_caret_) {
234     switch (PRIMARYLANGID(input_language_id_)) {
235       case LANG_JAPANESE:
236         ::SetCaretPos(x, y + caret_rect_.height());
237         break;
238       default:
239         ::SetCaretPos(x, y);
240         break;
241     }
242   }
243   if (use_composition_window_) {
244     // Moves the composition text window.
245     COMPOSITIONFORM cf = {CFS_POINT, {x, y}};
246     ::ImmSetCompositionWindow(imm_context, &cf);
247     // Don't need to set the position of candidate window.
248     return;
249   }
250 
251   if (PRIMARYLANGID(input_language_id_) == LANG_KOREAN) {
252     // Chinese IMEs and Japanese IMEs require the upper-left corner of
253     // the caret to move the position of their candidate windows.
254     // On the other hand, Korean IMEs require the lower-left corner of the
255     // caret to move their candidate windows.
256     y += kCaretMargin;
257   }
258   // Japanese IMEs and Korean IMEs also use the rectangle given to
259   // ::ImmSetCandidateWindow() with its 'dwStyle' parameter CFS_EXCLUDE
260   // to move their candidate windows when a user disables TSF and CUAS.
261   // Therefore, we also set this parameter here.
262   CANDIDATEFORM exclude_rectangle = {0, CFS_EXCLUDE, {x, y},
263       {x, y, x + caret_rect_.width(), y + caret_rect_.height()}};
264   ::ImmSetCandidateWindow(imm_context, &exclude_rectangle);
265 }
266 
UpdateImeWindow(HWND window_handle)267 void IMM32Manager::UpdateImeWindow(HWND window_handle) {
268   // Just move the IME window attached to the given window.
269   if (caret_rect_.x() >= 0 && caret_rect_.y() >= 0) {
270     HIMC imm_context = ::ImmGetContext(window_handle);
271     if (imm_context) {
272       MoveImeWindow(window_handle, imm_context);
273       ::ImmReleaseContext(window_handle, imm_context);
274     }
275   }
276 }
277 
CleanupComposition(HWND window_handle)278 void IMM32Manager::CleanupComposition(HWND window_handle) {
279   // Notify the IMM attached to the given window to complete the ongoing
280   // composition, (this case happens when the given window is de-activated
281   // while composing a text and re-activated), and reset the omposition status.
282   if (is_composing_) {
283     HIMC imm_context = ::ImmGetContext(window_handle);
284     if (imm_context) {
285       ::ImmNotifyIME(imm_context, NI_COMPOSITIONSTR, CPS_COMPLETE, 0);
286       ::ImmReleaseContext(window_handle, imm_context);
287     }
288     ResetComposition(window_handle);
289   }
290 }
291 
ResetComposition(HWND window_handle)292 void IMM32Manager::ResetComposition(HWND window_handle) {
293   // Currently, just reset the composition status.
294   is_composing_ = false;
295 }
296 
CompleteComposition(HWND window_handle,HIMC imm_context)297 void IMM32Manager::CompleteComposition(HWND window_handle, HIMC imm_context) {
298   // We have to confirm there is an ongoing composition before completing it.
299   // This is for preventing some IMEs from getting confused while completing an
300   // ongoing composition even if they do not have any ongoing compositions.)
301   if (is_composing_) {
302     ::ImmNotifyIME(imm_context, NI_COMPOSITIONSTR, CPS_COMPLETE, 0);
303     ResetComposition(window_handle);
304   }
305 }
306 
GetCompositionInfo(HIMC imm_context,LPARAM lparam,CompositionText * composition)307 void IMM32Manager::GetCompositionInfo(HIMC imm_context, LPARAM lparam,
308                                   CompositionText* composition) {
309   // We only care about GCS_COMPATTR, GCS_COMPCLAUSE and GCS_CURSORPOS, and
310   // convert them into underlines and selection range respectively.
311   composition->underlines.clear();
312 
313   int length = static_cast<int>(composition->text.length());
314 
315   // Find out the range selected by the user.
316   int target_start = length;
317   int target_end = length;
318   if (lparam & GCS_COMPATTR)
319     GetCompositionTargetRange(imm_context, &target_start, &target_end);
320 
321   // Retrieve the selection range information. If CS_NOMOVECARET is specified,
322   // that means the cursor should not be moved, then we just place the caret at
323   // the beginning of the composition string. Otherwise we should honour the
324   // GCS_CURSORPOS value if it's available.
325   // TODO(suzhe): due to a bug of webkit, we currently can't use selection range
326   // with composition string. See: https://bugs.webkit.org/show_bug.cgi?id=40805
327   if (!(lparam & CS_NOMOVECARET) && (lparam & GCS_CURSORPOS)) {
328     // IMM32 does not support non-zero-width selection in a composition. So
329     // always use the caret position as selection range.
330     int cursor = ::ImmGetCompositionString(imm_context, GCS_CURSORPOS, NULL, 0);
331     composition->selection = gfx::Range(cursor);
332   } else {
333     composition->selection = gfx::Range(0);
334   }
335 
336   // Retrieve the clause segmentations and convert them to underlines.
337   if (lparam & GCS_COMPCLAUSE) {
338     GetCompositionUnderlines(imm_context, target_start, target_end,
339                              &composition->underlines);
340   }
341 
342   // Set default underlines in case there is no clause information.
343   if (!composition->underlines.size()) {
344     CompositionUnderline underline;
345     underline.color = SK_ColorBLACK;
346     underline.background_color = SK_ColorTRANSPARENT;
347     if (target_start > 0) {
348       underline.start_offset = 0U;
349       underline.end_offset = static_cast<uint32>(target_start);
350       underline.thick = false;
351       composition->underlines.push_back(underline);
352     }
353     if (target_end > target_start) {
354       underline.start_offset = static_cast<uint32>(target_start);
355       underline.end_offset = static_cast<uint32>(target_end);
356       underline.thick = true;
357       composition->underlines.push_back(underline);
358     }
359     if (target_end < length) {
360       underline.start_offset = static_cast<uint32>(target_end);
361       underline.end_offset = static_cast<uint32>(length);
362       underline.thick = false;
363       composition->underlines.push_back(underline);
364     }
365   }
366 }
367 
GetString(HIMC imm_context,WPARAM lparam,int type,base::string16 * result)368 bool IMM32Manager::GetString(HIMC imm_context,
369                          WPARAM lparam,
370                          int type,
371                          base::string16* result) {
372   if (!(lparam & type))
373     return false;
374   LONG string_size = ::ImmGetCompositionString(imm_context, type, NULL, 0);
375   if (string_size <= 0)
376     return false;
377   DCHECK_EQ(0u, string_size % sizeof(wchar_t));
378   ::ImmGetCompositionString(imm_context, type,
379       WriteInto(result, (string_size / sizeof(wchar_t)) + 1), string_size);
380   return true;
381 }
382 
GetResult(HWND window_handle,LPARAM lparam,base::string16 * result)383 bool IMM32Manager::GetResult(
384     HWND window_handle, LPARAM lparam, base::string16* result) {
385   bool ret = false;
386   HIMC imm_context = ::ImmGetContext(window_handle);
387   if (imm_context) {
388     ret = GetString(imm_context, lparam, GCS_RESULTSTR, result);
389     ::ImmReleaseContext(window_handle, imm_context);
390   }
391   return ret;
392 }
393 
GetComposition(HWND window_handle,LPARAM lparam,CompositionText * composition)394 bool IMM32Manager::GetComposition(HWND window_handle, LPARAM lparam,
395                               CompositionText* composition) {
396   bool ret = false;
397   HIMC imm_context = ::ImmGetContext(window_handle);
398   if (imm_context) {
399     // Copy the composition string to the CompositionText object.
400     ret = GetString(imm_context, lparam, GCS_COMPSTR, &composition->text);
401 
402     if (ret) {
403       // This is a dirty workaround for facebook. Facebook deletes the
404       // placeholder character (U+3000) used by Traditional-Chinese IMEs at the
405       // beginning of composition text. This prevents WebKit from replacing this
406       // placeholder character with a Traditional-Chinese character, i.e. we
407       // cannot input any characters in a comment box of facebook with
408       // Traditional-Chinese IMEs. As a workaround, we replace U+3000 at the
409       // beginning of composition text with U+FF3F, a placeholder character used
410       // by Japanese IMEs.
411       if (input_language_id_ == MAKELANGID(LANG_CHINESE,
412                                            SUBLANG_CHINESE_TRADITIONAL) &&
413           composition->text[0] == 0x3000) {
414         composition->text[0] = 0xFF3F;
415       }
416 
417       // Retrieve the composition underlines and selection range information.
418       GetCompositionInfo(imm_context, lparam, composition);
419 
420       // Mark that there is an ongoing composition.
421       is_composing_ = true;
422     }
423 
424     ::ImmReleaseContext(window_handle, imm_context);
425   }
426   return ret;
427 }
428 
DisableIME(HWND window_handle)429 void IMM32Manager::DisableIME(HWND window_handle) {
430   // A renderer process have moved its input focus to a password input
431   // when there is an ongoing composition, e.g. a user has clicked a
432   // mouse button and selected a password input while composing a text.
433   // For this case, we have to complete the ongoing composition and
434   // clean up the resources attached to this object BEFORE DISABLING THE IME.
435   CleanupComposition(window_handle);
436   ::ImmAssociateContextEx(window_handle, NULL, 0);
437 }
438 
CancelIME(HWND window_handle)439 void IMM32Manager::CancelIME(HWND window_handle) {
440   if (is_composing_) {
441     HIMC imm_context = ::ImmGetContext(window_handle);
442     if (imm_context) {
443       ::ImmNotifyIME(imm_context, NI_COMPOSITIONSTR, CPS_CANCEL, 0);
444       ::ImmReleaseContext(window_handle, imm_context);
445     }
446     ResetComposition(window_handle);
447   }
448 }
449 
EnableIME(HWND window_handle)450 void IMM32Manager::EnableIME(HWND window_handle) {
451   // Load the default IME context.
452   // NOTE(hbono)
453   //   IMM ignores this call if the IME context is loaded. Therefore, we do
454   //   not have to check whether or not the IME context is loaded.
455   ::ImmAssociateContextEx(window_handle, NULL, IACE_DEFAULT);
456 }
457 
UpdateCaretRect(HWND window_handle,const gfx::Rect & caret_rect)458 void IMM32Manager::UpdateCaretRect(HWND window_handle,
459                                const gfx::Rect& caret_rect) {
460   // Save the caret position, and Update the position of the IME window.
461   // This update is used for moving an IME window when a renderer process
462   // resize/moves the input caret.
463   if (caret_rect_ != caret_rect) {
464     caret_rect_ = caret_rect;
465     // Move the IME windows.
466     HIMC imm_context = ::ImmGetContext(window_handle);
467     if (imm_context) {
468       MoveImeWindow(window_handle, imm_context);
469       ::ImmReleaseContext(window_handle, imm_context);
470     }
471   }
472 }
473 
SetUseCompositionWindow(bool use_composition_window)474 void IMM32Manager::SetUseCompositionWindow(bool use_composition_window) {
475   use_composition_window_ = use_composition_window;
476 }
477 
GetInputLanguageName() const478 std::string IMM32Manager::GetInputLanguageName() const {
479   const LCID locale_id = MAKELCID(input_language_id_, SORT_DEFAULT);
480   // max size for LOCALE_SISO639LANGNAME and LOCALE_SISO3166CTRYNAME is 9.
481   wchar_t buffer[9];
482 
483   // Get language id.
484   int length = ::GetLocaleInfo(locale_id, LOCALE_SISO639LANGNAME, &buffer[0],
485                                arraysize(buffer));
486   if (length <= 1)
487     return std::string();
488 
489   std::string language;
490   base::WideToUTF8(buffer, length - 1, &language);
491   if (SUBLANGID(input_language_id_) == SUBLANG_NEUTRAL)
492     return language;
493 
494   // Get region id.
495   length = ::GetLocaleInfo(locale_id, LOCALE_SISO3166CTRYNAME, &buffer[0],
496                            arraysize(buffer));
497   if (length <= 1)
498     return language;
499 
500   std::string region;
501   base::WideToUTF8(buffer, length - 1, &region);
502   return language.append(1, '-').append(region);
503 }
504 
SetTextInputMode(HWND window_handle,TextInputMode input_mode)505 void IMM32Manager::SetTextInputMode(HWND window_handle,
506                                     TextInputMode input_mode) {
507   if (input_mode == ui::TEXT_INPUT_MODE_DEFAULT)
508     return;
509 
510   const HIMC imm_context = ::ImmGetContext(window_handle);
511   if (!imm_context)
512     return;
513 
514   DWORD conversion_mode = 0;
515   DWORD sentence_mode = 0;
516   if (::ImmGetConversionStatus(imm_context, &conversion_mode, &sentence_mode)
517       == FALSE) {
518     return;
519   }
520 
521   BOOL open = FALSE;
522   ConvertInputModeToImmFlags(input_mode, conversion_mode, &open,
523                              &conversion_mode),
524 
525   ::ImmSetOpenStatus(imm_context, open);
526   if (open)
527     ::ImmSetConversionStatus(imm_context, conversion_mode, sentence_mode);
528   ::ImmReleaseContext(window_handle, imm_context);
529 }
530 
531 // static
IsRTLKeyboardLayoutInstalled()532 bool IMM32Manager::IsRTLKeyboardLayoutInstalled() {
533   static enum {
534     RTL_KEYBOARD_LAYOUT_NOT_INITIALIZED,
535     RTL_KEYBOARD_LAYOUT_INSTALLED,
536     RTL_KEYBOARD_LAYOUT_NOT_INSTALLED,
537     RTL_KEYBOARD_LAYOUT_ERROR,
538   } layout = RTL_KEYBOARD_LAYOUT_NOT_INITIALIZED;
539 
540   // Cache the result value.
541   if (layout != RTL_KEYBOARD_LAYOUT_NOT_INITIALIZED)
542     return layout == RTL_KEYBOARD_LAYOUT_INSTALLED;
543 
544   // Retrieve the number of layouts installed in this system.
545   int size = GetKeyboardLayoutList(0, NULL);
546   if (size <= 0) {
547     layout = RTL_KEYBOARD_LAYOUT_ERROR;
548     return false;
549   }
550 
551   // Retrieve the keyboard layouts in an array and check if there is an RTL
552   // layout in it.
553   scoped_ptr<HKL[]> layouts(new HKL[size]);
554   ::GetKeyboardLayoutList(size, layouts.get());
555   for (int i = 0; i < size; ++i) {
556     if (IsRTLPrimaryLangID(PRIMARYLANGID(layouts[i]))) {
557       layout = RTL_KEYBOARD_LAYOUT_INSTALLED;
558       return true;
559     }
560   }
561 
562   layout = RTL_KEYBOARD_LAYOUT_NOT_INSTALLED;
563   return false;
564 }
565 
IsCtrlShiftPressed(base::i18n::TextDirection * direction)566 bool IMM32Manager::IsCtrlShiftPressed(base::i18n::TextDirection* direction) {
567   uint8_t keystate[256];
568   if (!::GetKeyboardState(&keystate[0]))
569     return false;
570 
571   // To check if a user is pressing only a control key and a right-shift key
572   // (or a left-shift key), we use the steps below:
573   // 1. Check if a user is pressing a control key and a right-shift key (or
574   //    a left-shift key).
575   // 2. If the condition 1 is true, we should check if there are any other
576   //    keys pressed at the same time.
577   //    To ignore the keys checked in 1, we set their status to 0 before
578   //    checking the key status.
579   const int kKeyDownMask = 0x80;
580   if ((keystate[VK_CONTROL] & kKeyDownMask) == 0)
581     return false;
582 
583   if (keystate[VK_RSHIFT] & kKeyDownMask) {
584     keystate[VK_RSHIFT] = 0;
585     *direction = base::i18n::RIGHT_TO_LEFT;
586   } else if (keystate[VK_LSHIFT] & kKeyDownMask) {
587     keystate[VK_LSHIFT] = 0;
588     *direction = base::i18n::LEFT_TO_RIGHT;
589   } else {
590     return false;
591   }
592 
593   // Scan the key status to find pressed keys. We should abandon changing the
594   // text direction when there are other pressed keys.
595   // This code is executed only when a user is pressing a control key and a
596   // right-shift key (or a left-shift key), i.e. we should ignore the status of
597   // the keys: VK_SHIFT, VK_CONTROL, VK_RCONTROL, and VK_LCONTROL.
598   // So, we reset their status to 0 and ignore them.
599   keystate[VK_SHIFT] = 0;
600   keystate[VK_CONTROL] = 0;
601   keystate[VK_RCONTROL] = 0;
602   keystate[VK_LCONTROL] = 0;
603   // Oddly, pressing F10 in another application seemingly breaks all subsequent
604   // calls to GetKeyboardState regarding the state of the F22 key. Perhaps this
605   // defect is limited to my keyboard driver, but ignoring F22 should be okay.
606   keystate[VK_F22] = 0;
607   for (int i = 0; i <= VK_PACKET; ++i) {
608     if (keystate[i] & kKeyDownMask)
609       return false;
610   }
611   return true;
612 }
613 
ConvertInputModeToImmFlags(TextInputMode input_mode,DWORD initial_conversion_mode,BOOL * open,DWORD * new_conversion_mode)614 void IMM32Manager::ConvertInputModeToImmFlags(TextInputMode input_mode,
615                                               DWORD initial_conversion_mode,
616                                               BOOL* open,
617                                               DWORD* new_conversion_mode) {
618   *open = TRUE;
619   *new_conversion_mode = initial_conversion_mode;
620   switch (input_mode) {
621     case ui::TEXT_INPUT_MODE_FULL_WIDTH_LATIN:
622       *new_conversion_mode |= IME_CMODE_FULLSHAPE;
623       *new_conversion_mode &= ~(IME_CMODE_NATIVE
624                               | IME_CMODE_KATAKANA);
625       break;
626     case ui::TEXT_INPUT_MODE_KANA:
627       *new_conversion_mode |= (IME_CMODE_NATIVE
628                              | IME_CMODE_FULLSHAPE);
629       *new_conversion_mode &= ~IME_CMODE_KATAKANA;
630       break;
631     case ui::TEXT_INPUT_MODE_KATAKANA:
632       *new_conversion_mode |= (IME_CMODE_NATIVE
633                              | IME_CMODE_KATAKANA
634                              | IME_CMODE_FULLSHAPE);
635       break;
636     default:
637       *open = FALSE;
638       break;
639   }
640 }
641 
642 }  // namespace ui
643