Fixing Configuration Inconsistencies across File Type Boundaries

Abstract

Creating a valid software configuration often involves multiple configuration file types, such as feature models, domain-specific languages, or C header files with preprocessor defines. Enforcing constraints across file types boundaries already at configuration is necessary to prevent inconsistencies, which otherwise are costly to discover and resolve later on. We present a pragmatic framework to specify and apply inconsistency-resolving fixes on configuration files of arbitrary types. The framework converts each configuration file to a model, checks it for consistency, applies fixes, and serializes it back again. We argue that conventionally programmed fixes and round-trip mechanisms (i.e., converters and serializers) are indispensable for practical applicability and can provide sufficient reliability when following usual development practices. We have developed round-trip mechanisms for seven different configuration file types and two fixing mechanisms. One fixing mechanism extends previous work by combining automatic detection of correct fix locations with a marker mechanism that reduces the number of locations. A tool-supported process for applying the fixes provides user guidance and integrates additional semantic validity checks on serialized configuration files of complex types (e.g., feature models). Evaluations reveal a speed up in inconsistency fixing and that the performance of the currently integrated round-tripping and fixing mechanisms is competitive.