From d8d9844b299bb9c91a35025f87a079f04c30eae9 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Thu, 20 Jan 2011 15:06:09 +0000
Subject: [PATCH] Further improve caching of locale-specific data in
 wxNumberFormatter.

Also update the cached data if setlocale() was called explicitly instead of
using wxLocale to change the locale because at least under Unix systems
calling setlocale() changes the result of wxLocale::GetInfo() and so the
result returned by wxNumberFormatter::GetDecimalSeparator() and
GetThousandsSeparatorIfUsed() could be inconsistent with the locale being
really used.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66726 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 src/common/numformatter.cpp | 81 ++++++++++++++++++++++++++++++++-----
 1 file changed, 71 insertions(+), 10 deletions(-)

diff --git a/src/common/numformatter.cpp b/src/common/numformatter.cpp
index 5422984ec3..898c1cf933 100644
--- a/src/common/numformatter.cpp
+++ b/src/common/numformatter.cpp
@@ -21,6 +21,73 @@
 #include "wx/numformatter.h"
 #include "wx/intl.h"
 
+// ----------------------------------------------------------------------------
+// local helpers
+// ----------------------------------------------------------------------------
+
+namespace
+{
+
+// Contains information about the locale which was used to initialize our
+// cached values of the decimal and thousands separators. Notice that it isn't
+// enough to store just wxLocale because the user code may call setlocale()
+// directly and storing just C locale string is not enough because we can use
+// the OS API directly instead of the CRT ones on some platforms. So just store
+// both.
+class LocaleId
+{
+public:
+    LocaleId()
+    {
+        m_wxloc = NULL;
+        m_cloc = NULL;
+    }
+
+    ~LocaleId()
+    {
+        Free();
+    }
+
+    // Return true if this is the first time this function is called for this
+    // object or if the program locale has changed since the last time it was
+    // called. Otherwise just return false indicating that updating locale-
+    // dependent information is not necessary.
+    bool NotInitializedOrHasChanged()
+    {
+        wxLocale * const wxloc = wxGetLocale();
+        const char * const cloc = setlocale(LC_ALL, NULL);
+        if ( m_wxloc || m_cloc )
+        {
+            if ( m_wxloc == wxloc && strcmp(m_cloc, cloc) == 0 )
+                return false;
+
+            Free();
+        }
+        //else: Not initialized yet.
+
+        m_wxloc = wxloc;
+        m_cloc = wxCRT_StrdupA(cloc);
+
+        return true;
+    }
+
+private:
+    void Free()
+    {
+        free(m_cloc);
+    }
+
+    // Non-owned pointer to wxLocale which was used.
+    wxLocale *m_wxloc;
+
+    // Owned pointer to the C locale string.
+    char *m_cloc;
+
+    wxDECLARE_NO_COPY_CLASS(LocaleId);
+};
+
+} // anonymous namespace
+
 // ============================================================================
 // wxNumberFormatter implementation
 // ============================================================================
@@ -38,9 +105,9 @@ wxChar wxNumberFormatter::GetDecimalSeparator()
 
     // Remember the locale which was current when we initialized, we must redo
     // the initialization if the locale changed.
-    static wxLocale *s_localeUsedForInit = NULL;
+    static LocaleId s_localeUsedForInit;
 
-    if ( !s_decimalSeparator || (s_localeUsedForInit != wxGetLocale()) )
+    if ( s_localeUsedForInit.NotInitializedOrHasChanged() )
     {
         const wxString
             s = wxLocale::GetInfo(wxLOCALE_DECIMAL_POINT, wxLOCALE_CAT_NUMBER);
@@ -58,8 +125,6 @@ wxChar wxNumberFormatter::GetDecimalSeparator()
 
             s_decimalSeparator = s[0];
         }
-
-        s_localeUsedForInit = wxGetLocale();
     }
 
     return s_decimalSeparator;
@@ -68,10 +133,9 @@ wxChar wxNumberFormatter::GetDecimalSeparator()
 bool wxNumberFormatter::GetThousandsSeparatorIfUsed(wxChar *sep)
 {
     static wxChar s_thousandsSeparator = 0;
-    static bool s_initialized = false;
-    static wxLocale *s_localeUsedForInit = NULL;
+    static LocaleId s_localeUsedForInit;
 
-    if ( !s_initialized || (s_localeUsedForInit != wxGetLocale()) )
+    if ( s_localeUsedForInit.NotInitializedOrHasChanged() )
     {
         const wxString
             s = wxLocale::GetInfo(wxLOCALE_THOUSANDS_SEP, wxLOCALE_CAT_NUMBER);
@@ -84,9 +148,6 @@ bool wxNumberFormatter::GetThousandsSeparatorIfUsed(wxChar *sep)
         }
         //else: Unlike above it's perfectly fine for the thousands separator to
         //      be empty if grouping is not used, so just leave it as 0.
-
-        s_initialized = true;
-        s_localeUsedForInit = wxGetLocale();
     }
 
     if ( !s_thousandsSeparator )
-- 
2.45.2