colormanager: always temporarily set C locale when loading an OCIO config from file

Fixes known bug in OCIO when loading files from non-English locales.

app/dialog/projectproperties/projectproperties.cpp

@@ -177,7 +177,7 @@ void ProjectPropertiesDialog::OCIOFilenameUpdated()
     if (ocio_filename_->text().isEmpty()) {
       c = ColorManager::GetDefaultConfig();
     } else {
-      c = OCIO::Config::CreateFromFile(ocio_filename_->text().toUtf8());
+      c = ColorManager::CreateConfigFromFile(ocio_filename_->text());
     }
 
     ocio_filename_->setStyleSheet(QString());

app/render/colormanager.cpp

@@ -49,6 +49,13 @@ OCIO::ConstConfigRcPtr ColorManager::GetConfig() const
   return config_;
 }
 
+OCIO::ConstConfigRcPtr ColorManager::CreateConfigFromFile(const QString &filename)
+{
+  SetCLocale();
+
+  return OCIO::Config::CreateFromFile(filename.toUtf8());
+}
+
 const QString &ColorManager::GetConfigFilename() const
 {
   return config_filename_;
@@ -62,7 +69,9 @@ OCIO::ConstConfigRcPtr ColorManager::GetDefaultConfig()
 void ColorManager::SetUpDefaultConfig()
 {
   if (!qgetenv("OCIO").isEmpty()) {
+    // Attempt to set config from "OCIO" environment variable
     try {
+      SetCLocale();
       default_config_ = OCIO::Config::CreateFromEnv();
 
       return;
@@ -71,7 +80,7 @@ void ColorManager::SetUpDefaultConfig()
     }
   }
 
-  // Kind of hacky, but it'll work
+  // Extract OCIO config - kind of hacky, but it'll work
   QString dir = QDir(FileFunctions::GetTempFilePath()).filePath(QStringLiteral("ocioconf"));
 
   FileFunctions::CopyDirectory(QStringLiteral(":/ocioconf"),
@@ -80,7 +89,7 @@ void ColorManager::SetUpDefaultConfig()
 
   qDebug() << "Extracting default OCIO config to" << dir;
 
-  default_config_ = OCIO::Config::CreateFromFile(QDir(dir).filePath(QStringLiteral("config.ocio")).toUtf8());
+  default_config_ = CreateConfigFromFile(QDir(dir).filePath(QStringLiteral("config.ocio")));
 }
 
 void ColorManager::SetConfig(const QString &filename)

app/render/colormanager.h

@@ -36,6 +36,8 @@ public:
 
   OCIO::ConstConfigRcPtr GetConfig() const;
 
+  static OCIO::ConstConfigRcPtr CreateConfigFromFile(const QString& filename);
+
   const QString& GetConfigFilename() const;
 
   static OCIO::ConstConfigRcPtr GetDefaultConfig();
@@ -90,6 +92,53 @@ public:
 
   static void SetOCIOMethodForMode(RenderMode::Mode mode, OCIOMethod method);
 
+  class SetCLocale
+  {
+  public:
+    SetCLocale()
+    {
+#ifdef Q_OS_WINDOWS
+      // set locale will only change locale on the current thread
+      previousThreadConfig = _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
+
+      // get and store current locale
+      ssaLocale.convert(setlocale(LC_ALL, NULL));
+
+      // set to "C" locale
+      setlocale(LC_ALL, "C");
+#else
+      // set to C locale, saving the old one (returned from useLocale)
+      currentLocale = newlocale(LC_ALL_MASK,"C",NULL);
+      oldLocale = uselocale(currentLocale);
+#endif
+    }
+
+    ~SetCLocale()
+    {
+#ifdef Q_OS_WINDOWS
+      // thread specific
+      setlocale(LC_ALL, ssaLocale.c_str());
+
+      // set back to global settings]
+      _configthreadlocale(previousThreadConfig);
+#else
+      // restore the previous locale and freeing the created locale
+      uselocale(oldLocale);
+      freelocale(currentLocale);
+#endif
+    }
+
+  private:
+#ifdef Q_OS_WINDOWS
+    SoStringA ssaLocale;
+    int previousThreadConfig;
+#else
+    locale_t oldLocale;
+    locale_t currentLocale;
+#endif
+
+  };
+
 signals:
   void ConfigChanged();