Revert "Optimized QLocale to access system locale on demand."

The change introduces regression in QIntValidator and QInputDialog, which needs
to be addressed before pushing the change again.

Also reverted the following two compile fixes:
Revert "Don't use QSystemLocale if QT_NO_SYSTEMLOCALE (like QWS)"
Revert "Don't use QSystemLocale if QT_NO_SYSTEMLOCALE (like QWS)"

This reverts commit c786e0cd3c40193073ce2f59f98a4d83bbe1a9b9.
This reverts commit 9e5176070cdeba3e96f1969cfbb71bbd407a651e.
This reverts commit 8911ed8bfe7f918b93c758f9b5d93274b37739e6.

Reviewed-by: trustme

3 files changed, 46 insertions, 143 deletions

diff --git a/src/corelib/tools/qlocale.cpp b/src/corelib/tools/qlocale.cpp
index 9625228..ff10fa1 100644
--- a/src/corelib/tools/qlocale.cpp
+++ b/src/corelib/tools/qlocale.cpp
@@ -1274,25 +1274,11 @@ QLocale QSystemLocale::fallbackLocale() const
 */
 QVariant QSystemLocale::query(QueryType type, QVariant /* in */) const
 {
-    switch (type) {
-    case MeasurementSystem:
+    if (type == MeasurementSystem) {
         return QVariant(unixGetSystemMeasurementSystem());
-    case LanguageId:
-    case CountryId: {
-        QString locale = QLatin1String(envVarLocale());
-        QLocale::Language lang;
-        QLocale::Country cntry;
-        getLangAndCountry(locale, lang, cntry);
-        if (type == LanguageId)
-            return lang;
-        if (cntry == QLocale::AnyCountry)
-            return fallbackLocale().country();
-        return cntry;
-    }
-    default:
-        break;
+    } else {
+        return QVariant();
     }
-    return QVariant();
 }
 
 #elif !defined(Q_OS_SYMBIAN)
@@ -1324,10 +1310,12 @@ QVariant QSystemLocale::query(QueryType /* type */, QVariant /* in */) const
 
 #endif
 
+#ifndef QT_NO_SYSTEMLOCALE
 static QSystemLocale *_systemLocale = 0;
 Q_GLOBAL_STATIC_WITH_ARGS(QSystemLocale, QSystemLocale_globalSystemLocale, (true))
 static QLocalePrivate *system_lp = 0;
 Q_GLOBAL_STATIC(QLocalePrivate, globalLocalePrivate)
+#endif
 
 /******************************************************************************
 ** Default system locale behavior
@@ -1400,8 +1388,7 @@ QSystemLocale::QSystemLocale()
 
 /*! \internal */
 QSystemLocale::QSystemLocale(bool)
-{
-}
+{ }
 
 /*!
   Deletes the object.
@@ -1423,42 +1410,16 @@ static const QSystemLocale *systemLocale()
     return QSystemLocale_globalSystemLocale();
 }
 
-static const QLocalePrivate *maybeSystemPrivate();
-bool QLocalePrivate::isUninitializedSystemLocale() const
-{
-    return this == maybeSystemPrivate() && m_language_id == 0;
-}
-
-QVariant QLocalePrivate::querySystemLocale(int type, const QVariant &in) const
-{
-    QVariant res = systemLocale()->query(QSystemLocale::QueryType(type), in);
-    if (res.isNull() && isUninitializedSystemLocale()) {
-        // if we were not able to get data from the system, initialize the
-        // system locale private data (which is essentially equals to this)
-        // with a fallback locale.
-        QLocalePrivate *system_private = globalLocalePrivate();
-        *system_private = *systemLocale()->fallbackLocale().d();
-        // internal cache is not initialized with values from the system, mark
-        // it as not fully initialized system locale.
-        system_private->m_language_id = 0;
-    }
-    return res;
-}
-
-// retrieves data from the system locale and caches them locally.
 void QLocalePrivate::updateSystemPrivate()
 {
     const QSystemLocale *sys_locale = systemLocale();
     if (!system_lp)
-        return;
-
-    // copy over the information from the fallback locale and modify
+        system_lp = globalLocalePrivate();
     *system_lp = *sys_locale->fallbackLocale().d();
 
     QVariant res = sys_locale->query(QSystemLocale::LanguageId, QVariant());
     if (!res.isNull())
         system_lp->m_language_id = res.toInt();
-
     res = sys_locale->query(QSystemLocale::CountryId, QVariant());
     if (!res.isNull())
         system_lp->m_country_id = res.toInt();
@@ -1485,29 +1446,19 @@ void QLocalePrivate::updateSystemPrivate()
 }
 #endif
 
-// returns the private data for the system locale. Cached data will not be
-// initialized until the updateSystemPrivate is called.
 static const QLocalePrivate *systemPrivate()
 {
 #ifndef QT_NO_SYSTEMLOCALE
-    if (!system_lp) {
-        system_lp = globalLocalePrivate();
-        // mark the locale as uninitialized system locale
-        system_lp->m_language_id = 0;
-    }
+    // copy over the information from the fallback locale and modify
+    if (!system_lp || system_lp->m_language_id == 0)
+        QLocalePrivate::updateSystemPrivate();
+
     return system_lp;
 #else
     return locale_data;
 #endif
 }
 
-#ifndef QT_NO_SYSTEMLOCALE
-static const QLocalePrivate *maybeSystemPrivate()
-{
-    return system_lp;
-}
-#endif
-
 static const QLocalePrivate *defaultPrivate()
 {
     if (!default_lp)
@@ -2332,12 +2283,7 @@ void QLocale::setDefault(const QLocale &locale)
 */
 QLocale::Language QLocale::language() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return Language(dd->languageId());
+    return Language(d()->languageId());
 }
 
 /*!
@@ -2347,12 +2293,7 @@ QLocale::Language QLocale::language() const
 */
 QLocale::Country QLocale::country() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return Country(dd->countryId());
+    return Country(d()->countryId());
 }
 
 /*!
@@ -2690,8 +2631,8 @@ QString QLocale::toString(const QDate &date, FormatType format) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(format == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(format == LongFormat
                                              ? QSystemLocale::DateToStringLong : QSystemLocale::DateToStringShort,
                                              date);
         if (!res.isNull())
@@ -2785,8 +2726,8 @@ QString QLocale::toString(const QDateTime &dateTime, FormatType format) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(format == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(format == LongFormat
                                              ? QSystemLocale::DateTimeToStringLong
                                              : QSystemLocale::DateTimeToStringShort,
                                              dateTime);
@@ -2811,8 +2752,8 @@ QString QLocale::toString(const QTime &time, FormatType format) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(format == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(format == LongFormat
                                              ? QSystemLocale::TimeToStringLong : QSystemLocale::TimeToStringShort,
                                              time);
         if (!res.isNull())
@@ -2838,8 +2779,8 @@ QString QLocale::toString(const QTime &time, FormatType format) const
 QString QLocale::dateFormat(FormatType format) const
 {
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(format == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(format == LongFormat
                                              ? QSystemLocale::DateFormatLong : QSystemLocale::DateFormatShort,
                                              QVariant());
         if (!res.isNull())
@@ -2875,8 +2816,8 @@ QString QLocale::dateFormat(FormatType format) const
 QString QLocale::timeFormat(FormatType format) const
 {
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(format == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(format == LongFormat
                                              ? QSystemLocale::TimeFormatLong : QSystemLocale::TimeFormatShort,
                                              QVariant());
         if (!res.isNull())
@@ -2912,8 +2853,8 @@ QString QLocale::timeFormat(FormatType format) const
 QString QLocale::dateTimeFormat(FormatType format) const
 {
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(format == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(format == LongFormat
                                              ? QSystemLocale::DateTimeFormatLong
                                              : QSystemLocale::DateTimeFormatShort,
                                              QVariant());
@@ -3080,12 +3021,7 @@ QDateTime QLocale::toDateTime(const QString &string, const QString &format) cons
 */
 QChar QLocale::decimalPoint() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->decimal();
+    return d()->decimal();
 }
 
 /*!
@@ -3095,12 +3031,7 @@ QChar QLocale::decimalPoint() const
 */
 QChar QLocale::groupSeparator() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->group();
+    return d()->group();
 }
 
 /*!
@@ -3110,12 +3041,7 @@ QChar QLocale::groupSeparator() const
 */
 QChar QLocale::percent() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->percent();
+    return d()->percent();
 }
 
 /*!
@@ -3125,12 +3051,7 @@ QChar QLocale::percent() const
 */
 QChar QLocale::zeroDigit() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->zero();
+    return d()->zero();
 }
 
 /*!
@@ -3140,12 +3061,7 @@ QChar QLocale::zeroDigit() const
 */
 QChar QLocale::negativeSign() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->minus();
+    return d()->minus();
 }
 
 /*!
@@ -3155,12 +3071,7 @@ QChar QLocale::negativeSign() const
 */
 QChar QLocale::positiveSign() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->plus();
+    return d()->plus();
 }
 
 /*!
@@ -3170,12 +3081,7 @@ QChar QLocale::positiveSign() const
 */
 QChar QLocale::exponential() const
 {
-    const QLocalePrivate *dd = d();
-#ifndef QT_NO_SYSTEMLOCALE
-    if (dd->isUninitializedSystemLocale())
-        QLocalePrivate::updateSystemPrivate();
-#endif
-    return dd->exponential();
+    return d()->exponential();
 }
 
 static bool qIsUpper(char c)
@@ -3294,8 +3200,8 @@ QString QLocale::monthName(int month, FormatType type) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(type == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(type == LongFormat
                                              ? QSystemLocale::MonthNameLong : QSystemLocale::MonthNameShort,
                                              month);
         if (!res.isNull())
@@ -3340,8 +3246,8 @@ QString QLocale::standaloneMonthName(int month, FormatType type) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(type == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(type == LongFormat
                                              ? QSystemLocale::MonthNameLong : QSystemLocale::MonthNameShort,
                                              month);
         if (!res.isNull())
@@ -3387,8 +3293,8 @@ QString QLocale::dayName(int day, FormatType type) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(type == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(type == LongFormat
                                              ? QSystemLocale::DayNameLong : QSystemLocale::DayNameShort,
                                              day);
         if (!res.isNull())
@@ -3436,8 +3342,8 @@ QString QLocale::standaloneDayName(int day, FormatType type) const
         return QString();
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(type == LongFormat
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(type == LongFormat
                                              ? QSystemLocale::DayNameLong : QSystemLocale::DayNameShort,
                                              day);
         if (!res.isNull())
@@ -3481,8 +3387,8 @@ QLocale::MeasurementSystem QLocale::measurementSystem() const
     bool found = false;
 
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(QSystemLocale::MeasurementSystem, QVariant());
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(QSystemLocale::MeasurementSystem, QVariant());
         if (!res.isNull()) {
             meas = MeasurementSystem(res.toInt());
             found = true;
@@ -3509,8 +3415,8 @@ QLocale::MeasurementSystem QLocale::measurementSystem() const
 QString QLocale::amText() const
 {
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(QSystemLocale::AMText, QVariant());
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(QSystemLocale::AMText, QVariant());
         if (!res.isNull())
             return res.toString();
     }
@@ -3529,8 +3435,8 @@ QString QLocale::amText() const
 QString QLocale::pmText() const
 {
 #ifndef QT_NO_SYSTEMLOCALE
-    if (d() == maybeSystemPrivate()) {
-        QVariant res = d()->querySystemLocale(QSystemLocale::PMText, QVariant());
+    if (d() == systemPrivate()) {
+        QVariant res = systemLocale()->query(QSystemLocale::PMText, QVariant());
         if (!res.isNull())
             return res.toString();
     }
diff --git a/src/corelib/tools/qlocale.h b/src/corelib/tools/qlocale.h
index 9b7b214..e854c84 100644
--- a/src/corelib/tools/qlocale.h
+++ b/src/corelib/tools/qlocale.h
@@ -638,7 +638,6 @@ public:
         ;
 private:
     friend struct QLocalePrivate;
-
     // ### We now use this field to pack an index into locale_data and NumberOptions.
     // ### Qt 5: change to a QLocaleData *d; uint numberOptions.
     union {
diff --git a/src/corelib/tools/qlocale_p.h b/src/corelib/tools/qlocale_p.h
index 6c0935b..ecf79e9 100644
--- a/src/corelib/tools/qlocale_p.h
+++ b/src/corelib/tools/qlocale_p.h
@@ -132,8 +132,6 @@ public:
                           CharBuff *result) const;
     inline char digitToCLocale(const QChar &c) const;
 
-    inline bool isUninitializedSystemLocale() const;
-    QVariant querySystemLocale(int type, const QVariant &in) const;
     static void updateSystemPrivate();
 
     enum NumberMode { IntegerMode, DoubleStandardMode, DoubleScientificMode };