Generation of Code for Reading Data from the Declarative File Format Specifications Written in Language FlexT

摘要

The language FlexT (Flexible Types) is intended for specification of binary data formats. The language is declarative and designed to be well understood for human readers. Its main elements are the data type declarations, which look very much like the usual type declarations of the imperative programming languages, but are more flexible. While the primary purpose of the language FlexT development was to make the binary data understandable by displaying them according to the format specifications, recently we have implemented the code generator, which can produce data reading code in some imperative languages from the specifications. By now we have implemented the code generation for the most widely used FlexT data types, but some complex types like that used in specifications of machine instructions' encoding are not supported yet. The current capabilities of the code generator are well characterized by that it have successfully produced a full-featured data reader code for the well-known for the GIS community Shape file format. In the article we first give a review of the features of the modern projects oriented to specification of binary file formats and consider their code generation capabilities. Then we briefly review the main features of the FlexT language. Finally we describe the main approaches that we use for the code generation.