A Framework for Test Coverage of Safety and Mission Critical Software

Abstract

AbstractCode coverage assessment is an essential activity for ensuring the testing adequacy and qualification of any critical software. Flight software in Indian Space Research Organization (ISRO) launch vehicles is one such critical software element, where every functionality and portion of software has to be tested for clearing the software for a mission. The integrated system-level tests are very important for the qualification of the flight software. Since software testing is one of the time-consuming steps in software development life cycle, it is necessary to have automated coverage analyzers that can help in finding weakly and frequently executed code segments. They can be utilized for designing adequate number of test cases and optimizing the software for performance improvements. The automated coverage analyzers instrument the code for retrieving coverage information during execution of a test case. Coverage assessment of launch vehicle flight software in the integrated system test is a difficult task as code instrumentation affects the real-time performance of the system and the integrated tests fail to meet its objectives. Hence the software with instrumentation is executed in a standalone mode making use of the inputs tapped from the integrated tests without considering the real-time performance of timing but matching the functional outputs. Here open-source tools are used to carry out the code instrumentation. The end-to-end development carried out for assessing software coverage information of the integrated system test is described in this paper.KeywordsCode coverageSoftware testingSoftware instrumentationVerification and validationSoftware quality