Make _() and friends safe to call from any thread.

The GetUntranslatedString() hack keeps a global copy of all strings, so
that it can return a const reference as wxGetTranslation() return value.
A global wxHashSet instance shared by all threads won't do, even guarded
with a critical section, because it may internally copy values on any
insert and thus invalidate pointers that may still be used on another
thread.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74833 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -568,6 +568,7 @@ All:
 - Fix build with wxUSE_FFILE==0 (jroemmler).
 - Add wxDEPRECATED_MSG() and use it in a few places.
 - Return the old file descriptor/pointer from wx(F)File::Detach() (troelsk).
+- _() and wxGetTranslation() are now thread-safe.
 
 All (GUI):
 

include/wx/private/threadinfo.h

@@ -14,6 +14,13 @@
 
 class WXDLLIMPEXP_FWD_BASE wxLog;
 
+#if wxUSE_INTL
+#include "wx/hashset.h"
+WX_DECLARE_HASH_SET(wxString, wxStringHash, wxStringEqual,
+                    wxLocaleUntranslatedStrings);
+#endif
+
+
 // ----------------------------------------------------------------------------
 // wxThreadSpecificInfo: contains all thread-specific information used by wx
 // ----------------------------------------------------------------------------
@@ -40,6 +47,11 @@ public:
     //     logging
     bool loggingDisabled;
 
+#if wxUSE_INTL
+    // Storage for wxTranslations::GetUntranslatedString()
+    wxLocaleUntranslatedStrings untranslatedStrings;
+#endif
+
 private:
     wxThreadSpecificInfo() : logger(NULL), loggingDisabled(false) {}
 };

interface/wx/translation.h

@@ -234,6 +234,8 @@ public:
         error message is generated the first time a string is not found; use
         wxLogNull to suppress it).
 
+        This function is thread-safe.
+
         @remarks Domains are searched in the last to first order, i.e. catalogs
                  added later override those added before.
     */
@@ -264,6 +266,8 @@ public:
         See GNU gettext manual for additional information on plural forms handling.
         This method is called by the wxGetTranslation() function and _() macro.
 
+        This function is thread-safe.
+
         @remarks Domains are searched in the last to first order, i.e. catalogs
                  added later override those added before.
     */
@@ -515,6 +519,8 @@ public:
 
     This function calls wxTranslations::GetString().
 
+    This function is thread-safe.
+
     @note This function is not suitable for literal strings in Unicode builds
           since the literal strings must be enclosed in wxT() macro which makes
           them unrecognised by @c xgettext, and so they are not extracted to
@@ -546,7 +552,9 @@ const wxString& wxGetTranslation(const wxString& string,
     <http://www.gnu.org/software/gettext/manual/gettext.html#Plural-forms>
     For a shorter alternative see the wxPLURAL() macro.
 
-    This function calls wxLocale::GetString().
+    This function calls wxTranslation::GetString().
+
+    This function is thread-safe.
 
     @header{wx/intl.h}
 */
@@ -562,6 +570,8 @@ const wxString& wxGetTranslation(const wxString& string,
     also returns the translation of the string for the current locale during
     execution.
 
+    This macro is thread-safe.
+
     @header{wx/intl.h}
 */
 const wxString& _(const wxString& string);

src/common/translation.cpp

@@ -47,7 +47,7 @@
 #include "wx/tokenzr.h"
 #include "wx/fontmap.h"
 #include "wx/stdpaths.h"
-#include "wx/hashset.h"
+#include "wx/private/threadinfo.h"
 
 #ifdef __WINDOWS__
     #include "wx/dynlib.h"
@@ -1605,20 +1605,14 @@ wxString wxTranslations::GetBestTranslation(const wxString& domain,
 }
 
 
-namespace
-{
-WX_DECLARE_HASH_SET(wxString, wxStringHash, wxStringEqual,
-                    wxLocaleUntranslatedStrings);
-}
-
 /* static */
 const wxString& wxTranslations::GetUntranslatedString(const wxString& str)
 {
-    static wxLocaleUntranslatedStrings s_strings;
+    wxLocaleUntranslatedStrings& strings = wxThreadInfo.untranslatedStrings;
 
-    wxLocaleUntranslatedStrings::iterator i = s_strings.find(str);
-    if ( i == s_strings.end() )
-        return *s_strings.insert(str).first;
+    wxLocaleUntranslatedStrings::iterator i = strings.find(str);
+    if ( i == strings.end() )
+        return *strings.insert(str).first;
 
     return *i;
 }