fix CourseID::ToCourse for autogen courses

stepmania/src/CourseUtil.cpp

@@ -200,12 +200,21 @@ void CourseID::FromCourse( const Course *p )
 
 Course *CourseID::ToCourse() const
 {
-	Course* pCourse = NULL;
-	pCourse = SONGMAN->GetCourseFromPath( sPath );
-	if( pCourse ) 
-		return pCourse;
-	pCourse = SONGMAN->GetCourseFromName( sFullTitle );
-		return pCourse;
+	if( !sPath.empty() )
+	{
+		Course *pCourse = SONGMAN->GetCourseFromPath( sPath );
+		if( pCourse ) 
+			return pCourse;
+	}
+
+	if( !sFullTitle.empty() )
+	{
+		Course *pCourse = SONGMAN->GetCourseFromName( sFullTitle );
+		if( pCourse ) 
+			return pCourse;
+	}
+
+	return NULL;
 }
 
 XNode* CourseID::CreateNode() const

stepmania/src/SongManager.cpp

@@ -968,6 +968,9 @@ Song* SongManager::GetSongFromDir( CString sDir )
 
 Course* SongManager::GetCourseFromPath( CString sPath )
 {
+	if( sPath == "" )
+		return NULL;
+
 	for( unsigned int i=0; i<m_pCourses.size(); i++ )
 		if( sPath.CompareNoCase(m_pCourses[i]->m_sPath) == 0 )
 			return m_pCourses[i];
@@ -977,6 +980,9 @@ Course* SongManager::GetCourseFromPath( CString sPath )
 
 Course* SongManager::GetCourseFromName( CString sName )
 {
+	if( sName == "" )
+		return NULL;
+
 	for( unsigned int i=0; i<m_pCourses.size(); i++ )
 		if( sName.CompareNoCase(m_pCourses[i]->GetFullDisplayTitle()) == 0 )
 			return m_pCourses[i];