Store configuration files in a subdirectory

HowToBuild.md

@@ -122,7 +122,7 @@ $ ln -s ../../quickviewer/QuickViewer/translations translations
 
 ### For Windows
 
-- **[database]**
+- **[config/database]** or **[database]**
     - SQLite database which contains Catalogs and thumbnails
 - **[shaders]**
     - Fragment Shaders for image resizing (obsolete)
@@ -132,11 +132,16 @@ $ ln -s ../../quickviewer/QuickViewer/translations translations
     - Application main
 - **AssociateFilesWithQuickViewer.exe**
     - Set the association of image formats with UAC
-- **quickviewer.ini**
+- **[config/quickviewer.ini]** or **[quickviewer.ini]**
     - Main configuration file. Includes keyboard and mouse settings
-- **progress.ini**
+- **[config/progress.ini]** or **[progress.ini]**
     - Record the last displayed image in volume.
 
+The versions with **config** subdirectory are preferred due to their
+better security properties - the directory may be made writable without
+allowing modifications to the binary files. However, since they break
+compatibility with current installations, they are only used if the
+directory exists.
 
 ### For Linux (.AppImage)
 

QuickViewer/src/main.cpp

@@ -20,6 +20,10 @@ int main(int argc, char *argv[])
         // it must be set to the QT_QPA_PLATFORM environment variable before that.
 #  ifdef QV_PORTABLE
         QString inipath = QDir::toNativeSeparators(QFileInfo(argv[0]).path());
+        QDir iniSubDir = QDir(inipath + "\\" CONFIG_SUBDIR);
+        if (iniSubDir.exists()) {
+        	inipath += "\\" CONFIG_SUBDIR;
+        }
         inipath += "\\" APP_INI;
 #  else
         QString inipath = QDir(QStandardPaths::writableLocation(QStandardPaths::DataLocation)).filePath(APP_INI);

QuickViewer/src/models/qvapplication.cpp

@@ -96,6 +96,10 @@ QString QVApplication::getFilePathOfApplicationSetting(QString subFilePath)
 {
 #ifdef Q_OS_WIN
     if(m_portable) {
+        QDir settingsSubDir = getApplicationFilePath(QString("%1/" CONFIG_SUBDIR).arg(subFilePath));
+        if (settingsSubDir.exists()) {
+            return settingsSubDir;
+        }
         return getApplicationFilePath(subFilePath);
     } else {
         return QDir(QStandardPaths::writableLocation(QStandardPaths::DataLocation)).filePath(subFilePath);

QuickViewer/src/qv_init.h

@@ -9,6 +9,7 @@
 #define QV_THUMBNAILS "thumbnail.sqlite3.db"
 
 #ifdef Q_OS_WIN
+#define CONFIG_SUBDIR "config"
 #define APP_INI "quickviewer.ini"
 #define PROGRESS_INI "progress.ini"
 #define LINEFEED "\r\n"