avoid liblangtag processing for known locales, and know 'qtz'

For "simple" known (to us) locales avoid the overhead of liblangtag,
also in preparation of not having to initialize its database during
startup.

This also enables recognition of the 'qtz' pseudolocale for key ID
resources again, see fdo#57413

Change-Id: Id52a1ddc37b42063e3bf68a6dbeaeacfbfa704ef
(cherry picked from commit 4d24507451fbc2b7d72cf5f7048a424d52b63850)

1 files changed, 24 insertions, 4 deletions

diff --git a/i18npool/inc/i18npool/languagetag.hxx b/i18npool/inc/i18npool/languagetag.hxx
index 0b3eeddd150f..bb86b72262f0 100644
--- a/i18npool/inc/i18npool/languagetag.hxx
+++ b/i18npool/inc/i18npool/languagetag.hxx
@@ -229,6 +229,7 @@ private:
     mutable Decision                        meIsValid;
     mutable Decision                        meIsIsoLocale;
     mutable Decision                        meIsIsoODF;
+    mutable Decision                        meIsLiblangtagNeeded;   ///< whether processing with liblangtag needed
             bool                            mbSystemLocale      : 1;
     mutable bool                            mbInitializedBcp47  : 1;
     mutable bool                            mbInitializedLocale : 1;
@@ -245,17 +246,36 @@ private:
     void    convertLangToLocale();
     void    convertLangToBcp47();
 
-    bool    canonicalize() const;
+    bool    canonicalize();
 
-    rtl::OUString   getLanguageFromLangtag() const;
-    rtl::OUString   getScriptFromLangtag() const;
-    rtl::OUString   getRegionFromLangtag() const;
+    rtl::OUString   getLanguageFromLangtag();
+    rtl::OUString   getScriptFromLangtag();
+    rtl::OUString   getRegionFromLangtag();
 
     void            resetVars();
 
+    /** Obtain Language, Script and Country via simpleExtract() and assign them
+        to the cached variables if successful.
+
+        @return return of simpleExtract()
+     */
+    bool            cacheSimpleLSC();
+
     static bool     isIsoLanguage( const rtl::OUString& rLanguage );
     static bool     isIsoScript( const rtl::OUString& rScript );
     static bool     isIsoCountry( const rtl::OUString& rRegion );
+
+    /** Of a simple language tag of the form lll[-Ssss][-CC] (i.e. one that
+        would fulfill the isIsoODF() condition) extract the portions.
+
+        Does not check case or content!
+
+        @return TRUE if it detected a simple tag, else FALSE.
+     */
+    static bool     simpleExtract( const rtl::OUString& rBcp47,
+                                   rtl::OUString& rLanguage,
+                                   rtl::OUString& rScript,
+                                   rtl::OUString& rCountry );
 };
 
 #endif  // INCLUDED_I18NPOOL_LANGUAGETAG_HXX