Several fixes for thread_local_locale and strengthening test.

Author: stgates

Release/include/cpprest/asyncrt_utils.h

@@ -163,40 +163,72 @@ namespace details
     /// <summary>
     /// Cross platform RAII container for setting thread local locale.
     /// </summary>
+#ifdef _MS_WINDOWS
     class thread_local_locale
     {
     public:
-
         thread_local_locale(const char * locale)
         {
-#ifdef _MS_WINDOWS
-            _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
-            m_prevLocale = setlocale(LC_ALL, locale);
-#else
-            m_prevLocale = uselocale(newlocale(LC_ALL, locale, nullptr));        
-#endif
+            char *prevLocale = setlocale(LC_ALL, nullptr);
+            if (prevLocale == nullptr)
+            {
+                throw std::runtime_error("Unable to retrieve current locale.");
+            }
+            
+            // Copy to a string because later calls can invalidate the returned pointer.
+            m_prevLocale = prevLocale;
+            
+            m_prevThreadSetting = _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
+            if (m_prevThreadSetting == -1)
+            {
+                throw std::runtime_error("Unable to enable per thread locale.");
+            }
+            if (setlocale(LC_ALL, locale) == nullptr)
+            {
+                throw std::runtime_error("Unable to set locale");
+            }
         }
-
         ~thread_local_locale()
         {
-            if (m_prevLocale != nullptr)
-            {
-#ifdef _MS_WINDOWS
-                setlocale(LC_ALL, m_prevLocale);
+            setlocale(LC_ALL, m_prevLocale.c_str());
+            _configthreadlocale(m_prevThreadSetting);
+        }
+    private:
+        std::string m_prevLocale;
+        int m_prevThreadSetting;
+        thread_local_locale(const thread_local_locale &);
+        thread_local_locale & operator=(const thread_local_locale &);
+    };
 #else
-                locale_t original = uselocale(m_prevLocale);
+    class thread_local_locale
+    {
+    public:
+        thread_local_locale(const char * locale)
+        {
+            m_changedLocale = newlocale(LC_ALL, locale, nullptr);
+            if(m_changedLocale == nullptr)
+            {
+                throw std::runtime_error("Unable to create new locale.");
+            }
+            m_prevLocale = uselocale(original);
+            if(m_prevLocale == nullptr)
+            {
                 freelocale(original);
-#endif
+                throw std::runtime_error("Unable to set locale");
             }
         }
-
+        ~thread_local_locale()
+        {
+            uselocale(m_prevLocale);
+            freelocale(m_changedLocale);
+        }
     private:
-#ifdef _MS_WINDOWS
-        char * m_prevLocale;
-#else
         locale_t m_prevLocale;
-#endif
+        locale_t m_changedLocale;
+        thread_local_locale(const thread_local_locale &);
+        thread_local_locale & operator=(const thread_local_locale &);
     };
+#endif
 
     /// <summary>
     /// Our own implementation of alpha numeric instead of std::isalnum to avoid

Release/src/json/json.cpp

@@ -365,7 +365,7 @@ bool web::json::details::_Object::has_field(const utility::string_t &key) const
 
 utility::string_t json::value::to_string() const 
 { 
-    utility::details::thread_local_locale("C");
+    utility::details::thread_local_locale locale("C");
     return m_value->to_string(); 
 }
 

Release/src/json/json_serialization.cpp

@@ -41,7 +41,7 @@ using namespace utility::conversions;
 #ifdef _MS_WINDOWS
 void web::json::value::serialize(std::ostream& stream) const
 { 
-    utility::details::thread_local_locale("C");
+    utility::details::thread_local_locale locale("C");
 
     // This has better performance than writing directly to stream.
     std::string str;
@@ -56,7 +56,7 @@ void web::json::value::format(std::basic_string<wchar_t> &string) const
 
 void web::json::value::serialize(utility::ostream_t &stream) const 
 {
-    utility::details::thread_local_locale("C");
+    utility::details::thread_local_locale locale("C");
 
     // This has better performance than writing directly to stream.
     utility::string_t str;
@@ -238,6 +238,6 @@ utility::string_t web::json::value::as_string() const
 
 utility::string_t json::value::serialize() const 
 { 
-    utility::details::thread_local_locale("C");
+    utility::details::thread_local_locale locale("C");
     return m_value->to_string(); 
 }

Release/tests/Functional/json/parsing_tests.cpp

@@ -568,13 +568,20 @@ TEST(keep_order_while_parsing)
 
 TEST(non_default_locale)
 {
-    char * prevLocale = setlocale(LC_ALL, "fr-FR");
+    std::string originalLocale = setlocale(LC_ALL, nullptr);
+    std::string changedLocale("fr-FR");
+    setlocale(LC_ALL, changedLocale.c_str());
 
     // string serialize
     utility::string_t str(U("[true,false,-1.55,5,null,{\"abc\":5555}]"));
     json::value v = json::value::parse(str);
+    VERIFY_ARE_EQUAL(changedLocale, setlocale(LC_ALL, nullptr));
     VERIFY_ARE_EQUAL(str, v.serialize());
+    VERIFY_ARE_EQUAL(changedLocale, setlocale(LC_ALL, nullptr));
 
+    setlocale(LC_ALL, originalLocale.c_str());
+    setlocale(LC_NUMERIC, changedLocale.c_str());
+    
     // cpprestsdk stream serialize
     utility::stringstream_t stream;
     stream << v;
@@ -589,7 +596,7 @@ TEST(non_default_locale)
     stdStream >> stdStr;
     VERIFY_ARE_EQUAL(str, utility::conversions::to_string_t(stdStr));
 
-    setlocale(LC_ALL, prevLocale);
+    setlocale(LC_ALL, originalLocale.c_str());
 }
 
 } // SUITE(parsing_tests)