Collaborative Research: SHF: Medium: Precise Static Analysis of Event-based Systems

基于事件的编程用于构建拥有数十亿用户的软件系统，包括移动应用程序、Web客户端和服务器以及物联网设备。尽管基于事件的系统很受欢迎，但人们对它们的理解很少，而且容易出错，因为生成和调用事件的是底层平台，而不是程序。这些困难具有广泛的后果，如用户在移动应用程序中的工作丢失、网络服务中的静默错误或停机，以及意外的物联网设备行为。这个项目是(1)使基于事件的系统更易于分析，(2)在程序运行之前构建一种方法来提取某些关键事件之间的顺序，以防止排序错误，以及(3)允许对事件引起的易失性进行严格的推理，以防止诸如状态丢失和状态不一致等错误。该项目正在向学生介绍基于事件的系统可靠性的新方法，并为研究人员和软件开发人员提供分析此类系统的模型和基础设施。预计最终用户将受益于更可靠的基于事件的系统，无论是移动、浏览器/服务器还是物联网。该项目正在通过外展、指导和研究增加未被充分代表的群体对计算的参与。基于事件的系统继续飙升。这种范例的相对不确定性，加上基本的编程困难(如非确定性事件处理、异步状态操纵和状态破坏)，使健壮、可靠的应用程序的构建变得复杂。此外，还缺乏针对这一领域的程序分析方法和工具。为了解决这些问题，本项目正在引入程序分析基础和实用工具，如事件敏感度，使事件创建/启动成为程序分析的一级对象，并通过基于路径的事件排序实现精确分析。该项目旨在产生：静态分析，纳入上述改进，能够分析基于事件的应用程序；以及自动构建的平台模型(解决当前手动/特设平台模型中的不足，并旨在用于其他情况，例如，促进程序理解)。该项目的目标是Android移动平台、Java客户端和服务器程序，以及物联网应用。使用这些工具，开发人员和研究人员能够有效地洞察基于事件的应用程序，促进可靠应用程序的构建以及暴露现有程序中的不正确行为；这反过来又使基于事件的生态系统的用户受益。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Event-based programming is used to construct software systems withbillions of users, including mobile apps, Web clients and servers, andInternet-of-Things devices. Despite their popularity, event-basedsystems are poorly understood and prone to errors because theunderlying platform, not the program, generates and invokesevents. These difficulties have wide-ranging consequences such aslosing users' work in mobile apps, silent errors or downtime in Webservices, and unexpected Internet-of-Things device behavior. Thisproject is (1) making event-based systems easier to analyze, (2)constructing an approach for extracting order between certain key eventsbefore the program runs, to prevent ordering errors, and (3) allowingrigorous reasoning about event-induced volatility, to prevent errorssuch as state loss and state inconsistency. The project isintroducing students to new approaches to event-based systemreliability, as well as providing researchers and software developerswith models and infrastructure for analyzing such systems. End-usersare expected to benefit from more reliable event-based systems, whether mobile,browser/server, or Internet-of-Things. The project is increasing theparticipation of underrepresented groups in computing via outreach,mentoring, and research involvement.Event-based systems continue to surge in popularity. The relativenovelty of this paradigm, coupled with essential programmingdifficulties (such as non-deterministic event processing, asynchronousstate manipulation, and state destruction) complicate the constructionof robust, reliable applications. Furthermore, there is a shortage ofprogram-analysis approaches and tools for this space. To address theseissues, this project is introducing program-analysis foundations andpractical tools such as event sensitivity, making eventcreation/initiation a first-class object of program analysis, andallowing precise analysis via path-based event ordering. The projectis intended to result in: static analyses that incorporate the aforementionedadvances, enabling analysis of event-based applications; as well asautomatically-constructed platform models (which addressdeficiencies in current, manual/ad-hoc platform models, and are intended to beusable in other contexts, e.g., to facilitate programunderstanding). The project is targeting the Android mobile platform,JavaScript client and server programs, as well as Internet-of-Thingsapplications. Using these tools, developers and researchers areable to gain effective insights into event-based applicationsfacilitating the construction of reliable applications as well asexposing incorrect behavior in existing programs; this, in turn isbenefiting event-based ecosystems' users.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.