Design of Transmission Pipeline Modeling Language

General purpose software design and development involves the repetition of many processes, and the ability to automate these processes is often desired. To formalize a software process, such as modelling pipeline systems that transport fluids, an existing general purpose programming language (GPL) can be extended with its important aspects extracted as a model. However, the complexities and boundaries the programming language places on the ability to concisely and clearly describe the designing and modelling processes of the pipeline configurations can be difficult. The reality is that the library of a typical GPL Application Programmers Interface (API) constitutes class, method, and function names that become available only by object creation and method invocation, and as such cannot express domain concepts effectively. An alternative approach is to develop a language specifically for describing the processes. A language formalism that encourages domain specific development and as a tool for solving the complex problem of efficiently and effectively aiding the pipeline engineer in the design and implementation of pipeline configurations is presented in this paper. The language tool is used on the .Net platform for domain specific software development

Modular Abstract Definitional Interpreters for WebAssembly

Even though static analyses can improve performance and secure programs against vulnerabilities, no static whole-program analyses exist for WebAssembly (Wasm) to date. Part of the reason is that Wasm has many complex language concerns, and it is not obvious how to adopt existing analysis frameworks for these features. This paper explores how abstract definitional interpretation can be used to develop sophisticated analyses for Wasm and other complex languages efficiently. In particular, we show that the semantics of Wasm can be decomposed into 19 language-independent components that abstract different aspects of Wasm. We have written a highly configurable definitional interpreter for full Wasm 1.0 in 1628 LOC against these components. Analysis developers can instantiate this interpreter with different value and effect abstractions to obtain abstract definitional interpreters that compute inter-procedural control and data-flow information. This way, we develop the first whole-program dead code, constant propagation, and taint analyses for Wasm, each in less than 210 LOC. We evaluate our analyses on 1458 Wasm binaries collected by others in the wild. Our implementation is based on a novel framework for definitional abstract interpretation in Scala that eliminates scalability issues of prior work

A roadmap of problem frames research

It has been a decade since Michael Jackson introduced problem frames to the software engineering community. Since then, he has published further work addressing problem frames as well as presenting several keynote addresses. Other authors have researched problem frames, have written about their experiences and have expressed their opinions. It was not until 2004 that an opportunity presented itself for researchers in the field to gather as a community. The first International Workshop on Advances and Applications of Problem Frames (IWAAPF'04) was held at the International Conference on Software Engineering in Edinburgh on 24th May 2004. This event attracted over 30 participants: Jackson delivered a keynote address, researchers presented their work and an expert panel discussed the challenges of problem frames. Featuring in this special issue are two extended papers from the workshop, an invited contribution from Jackson in which he positions problem frames in the context of the software engineering discipline, and this article, where we provide a review of the literature

A Configuration Management System for Software Product Lines

Software product line engineering (SPLE) is a methodology for developing a family of software products in a particular domain by systematic reuse of shared code in order to improve product quality and reduce development time and cost. Currently, there are no software configuration management (SCM) tools that support software product line evolution. Conventional SCM tools are designed to support single product development. The use of conventional SCM tools forces developers to treat a software product line as a single software project by introducing new programming language constructs or using conditional compilation. We propose a research conguration management prototype called Molhado SPL that is designed specifically to support the evolution of software product lines. Molhado SPL addresses the evolution problem at the configuration level instead of at the code level. We studied the type of operations needed to support the evolution of software product lines and proposed a versioning model and eight cases of change propagation. Molhado SPL supports independent evolution of core assets and products, the sharing of code and the tracking relationships between products and shared code, and the eight cases of change propagation. The Molhado SPL consists of four layers with each layer providing a different type of service. At the heart of Molhado SPL are the versioning model, component object, shared component object, and project objects that allow for independent evolution of products and shared artifacts, for sharing, and for supporting change propagation. Furthermore,they allow product specific changes to shared code without interfering with the core asset that is shared. Products can also introduce product specific assets that only exist in that product. In order to for Molhado SPL to support product line, we implemented XML merging, feature model editing and debugging, and version-aware XML documents. To support merging of XML documents, we implemented a 3-way XML document merging algorithm that uses versioned data structures, change detection, and node identity. To support software product line derivation or modeling of software product line, we implemented support for feature model including editing and debugging. Finally, we created the version-aware XML document framework to support collaborative editing of XML documents without requiring a version repository. The version history is embedded in the documents using XML namespaces, so that the documents remain valid under the XML specification. The version-aware XML framework can also be used to support the exporting of documents from Molhado SPL repository to be edit outside and import back the change history made to the document. We evaluated Molhado SPL with two product lines: a document product line and a the graph data structures product line. This evaluation showed that Molhado SPL supports independently evolution of products and core assets and the eight change propagation cases. We did not evaluate MolhadoSPL in terms of scalability or usability. The main contributions of this dissertation research are: 1) Molhado SPL that supports the evolution of product lines, 2) a fast 3-way XML merge algorithm, 3) a version-aware XML document framework, and 4) a feature model editor and debugger