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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-

  *

  * This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 #include <stdio.h>

 #include "nsBidiKeyboard.h"

 #include "prmem.h"

 #include <tchar.h>

 NS_IMPL_ISUPPORTS(nsBidiKeyboard, nsIBidiKeyboard)

 nsBidiKeyboard::nsBidiKeyboard() : nsIBidiKeyboard()

 {

   Reset();

 }

 nsBidiKeyboard::~nsBidiKeyboard()

 {

 }

 NS_IMETHODIMP nsBidiKeyboard::Reset()

 {

   mInitialized = false;

   mHaveBidiKeyboards = false;

   mLTRKeyboard[0] = '\0';

   mRTLKeyboard[0] = '\0';

   mCurrentLocaleName[0] = '\0';

   return NS_OK;

 }

 NS_IMETHODIMP nsBidiKeyboard::IsLangRTL(bool *aIsRTL)

 {

   *aIsRTL = false;

   nsresult result = SetupBidiKeyboards();

   if (NS_FAILED(result))

     return result;

   HKL  currentLocale;

   currentLocale = ::GetKeyboardLayout(0);

   *aIsRTL = IsRTLLanguage(currentLocale);

   if (!::GetKeyboardLayoutNameW(mCurrentLocaleName))

     return NS_ERROR_FAILURE;

   NS_ASSERTION(*mCurrentLocaleName, 

     "GetKeyboardLayoutName return string length == 0");

   NS_ASSERTION((wcslen(mCurrentLocaleName) < KL_NAMELENGTH), 

     "GetKeyboardLayoutName return string length >= KL_NAMELENGTH");

   // The language set by the user overrides the default language for that direction

   if (*aIsRTL) {

     wcsncpy(mRTLKeyboard, mCurrentLocaleName, KL_NAMELENGTH);

     mRTLKeyboard[KL_NAMELENGTH-1] = '\0'; // null terminate

   } else {

     wcsncpy(mLTRKeyboard, mCurrentLocaleName, KL_NAMELENGTH);

     mLTRKeyboard[KL_NAMELENGTH-1] = '\0'; // null terminate

   }

   NS_ASSERTION((wcslen(mRTLKeyboard) < KL_NAMELENGTH), 

     "mLTRKeyboard has string length >= KL_NAMELENGTH");

   NS_ASSERTION((wcslen(mLTRKeyboard) < KL_NAMELENGTH), 

     "mRTLKeyboard has string length >= KL_NAMELENGTH");

   return NS_OK;

 }

 NS_IMETHODIMP nsBidiKeyboard::GetHaveBidiKeyboards(bool* aResult)

 {

   NS_ENSURE_ARG_POINTER(aResult);

   nsresult result = SetupBidiKeyboards();

   if (NS_FAILED(result))

     return result;

   *aResult = mHaveBidiKeyboards;

   return NS_OK;

 }

 // Get the list of keyboard layouts available in the system

 // Set mLTRKeyboard to the first LTR keyboard in the list and mRTLKeyboard to the first RTL keyboard in the list

 // These defaults will be used unless the user explicitly sets something else.

 nsresult nsBidiKeyboard::SetupBidiKeyboards()

 {

   if (mInitialized)

     return mHaveBidiKeyboards ? NS_OK : NS_ERROR_FAILURE;

   int keyboards;

   HKL far* buf;

   HKL locale;

   wchar_t localeName[KL_NAMELENGTH];

   bool isLTRKeyboardSet = false;

   bool isRTLKeyboardSet = false;

   // GetKeyboardLayoutList with 0 as first parameter returns the number of keyboard layouts available

   keyboards = ::GetKeyboardLayoutList(0, nullptr);

   if (!keyboards)

     return NS_ERROR_FAILURE;

   // allocate a buffer to hold the list

   buf = (HKL far*) PR_Malloc(keyboards * sizeof(HKL));

   if (!buf)

     return NS_ERROR_OUT_OF_MEMORY;

   // Call again to fill the buffer

   if (::GetKeyboardLayoutList(keyboards, buf) != keyboards) {

     PR_Free(buf);

     return NS_ERROR_UNEXPECTED;

   }

   // Go through the list and pick a default LTR and RTL keyboard layout

   while (keyboards--) {

     locale = buf[keyboards];

     if (IsRTLLanguage(locale)) {

       _snwprintf(mRTLKeyboard, KL_NAMELENGTH, L"%.*x", KL_NAMELENGTH - 1,

                  LANGIDFROMLCID((DWORD_PTR)locale));

       isRTLKeyboardSet = true;

     }

     else {

       _snwprintf(mLTRKeyboard, KL_NAMELENGTH, L"%.*x", KL_NAMELENGTH - 1,

                  LANGIDFROMLCID((DWORD_PTR)locale));

       isLTRKeyboardSet = true;

     }

   }

   PR_Free(buf);

   mInitialized = true;

   // If there is not at least one keyboard of each directionality, Bidi

   // keyboard functionality will be disabled.

   mHaveBidiKeyboards = (isRTLKeyboardSet && isLTRKeyboardSet);

   if (!mHaveBidiKeyboards)

     return NS_ERROR_FAILURE;

   // Get the current keyboard layout and use it for either mRTLKeyboard or

   // mLTRKeyboard as appropriate. If the user has many keyboard layouts

   // installed this prevents us from arbitrarily resetting the current

   // layout (bug 80274)

   locale = ::GetKeyboardLayout(0);

   if (!::GetKeyboardLayoutNameW(localeName))

     return NS_ERROR_FAILURE;

   NS_ASSERTION(*localeName, 

     "GetKeyboardLayoutName return string length == 0");

   NS_ASSERTION((wcslen(localeName) < KL_NAMELENGTH), 

     "GetKeyboardLayout return string length >= KL_NAMELENGTH");

   if (IsRTLLanguage(locale)) {

     wcsncpy(mRTLKeyboard, localeName, KL_NAMELENGTH);

     mRTLKeyboard[KL_NAMELENGTH-1] = '\0'; // null terminate

   }

   else {

     wcsncpy(mLTRKeyboard, localeName, KL_NAMELENGTH);

     mLTRKeyboard[KL_NAMELENGTH-1] = '\0'; // null terminate

   }

   NS_ASSERTION(*mRTLKeyboard, 

     "mLTRKeyboard has string length == 0");

   NS_ASSERTION(*mLTRKeyboard, 

     "mLTRKeyboard has string length == 0");

   return NS_OK;

 }

 // Test whether the language represented by this locale identifier is a

 //  right-to-left language, using bit 123 of the Unicode subset bitfield in

 //  the LOCALESIGNATURE

 // See http://msdn.microsoft.com/library/default.asp?url=/library/en-us/intl/unicode_63ub.asp

 bool nsBidiKeyboard::IsRTLLanguage(HKL aLocale)

 {

   LOCALESIGNATURE localesig;

   return (::GetLocaleInfoW(PRIMARYLANGID((DWORD_PTR)aLocale),

                            LOCALE_FONTSIGNATURE,

                            (LPWSTR)&localesig,

                            (sizeof(localesig)/sizeof(WCHAR))) &&

           (localesig.lsUsb[3] & 0x08000000));

 }