CPSC 421-010 Object-Oriented Programming (OOP) Spring 2024

Project 1: srcFacts Posted: Jan 25

One approach to understanding the source code of a system is to count things, e.g., the number of statements, functions, classes, expressions, LOC (Lines Of Code), etc. The program srcfacts produces a report of these counts.

It is very difficult for a program to parse the C++ source code directly, i.e., identify the syntactic parts of the code. So, the srcfacts program does not parse the C++ source code. It uses another tool, srcML, to convert the C++ source code into an XML format. The srcfacts program inputs this XML format, parses the XML while collecting counts of parts of the input code, and produces the report. The input has to be in the srcML format, e.g., demo.xml, however it can be compressed or part of an archive, e.g., demo.xml.zip, linux.xml.gz.

The srcfacts.cpp program is one large, main() function using almost no design features. It is extremely fast as, for example, it can produce a report on the entire Linux kernel in under 8 seconds. However, in its current form, it is not easy to debug the XML parsing, add additional program element counts, or even understand what is going on. It includes code for parsing all parts of XML, but it would not be easy to adapt the XML parsing code for another purpose, e.g., another report. The only way to reuse this code is by copy/paste reuse. Overall it has:

Your task is to take the srcFacts code, improve the overall design, and extract the XML parsing part of the code. When completed, a set of functions in the files xml_parser.hpp and xml_parser.cpp will handle as much XML parsing as possible, while the main program, srcfacts.cpp, generates the report using the XML parser functions for parsing.

• You do not have to understand how to parse XML. You are only repackaging XML parsing code, not writing from scratch.
• The existing code is brittle, so you need to work carefully not to break the code
• The repository includes example input
• Keep in mind all aspects of design as we discuss them in class

The steps (in order) with the associated (git) tag are:

Tag v1a: Without changing the design, add the code necessary for the report to include the number of return statements. The heading in the table must be "Returns". Due Jan 30

Tag v1b: Move the refillContent() function into the separate refillContent.hpp and refillContent.cpp files. Due Feb 2

Tag v1c: Apply the specific design changes from the Coding Practices Task List (to appear). As you verify that the code follows the practices given, check them off. Once you have completed all of them, close the issue. Due Feb 7 9

Tag v1d: Extract a set of (free) functions to handle the low-level details of the XML parsing. Extract one function at a time, i.e., each commit can only include a single extracted function. Due Feb 12

Tag v1e: Add the necessary code to count the number of line comments and the number of literal strings. The headings in the table must be "Line Comments" and "Strings". Due Feb 13 15

Your repository for this project is through GitHub Classroom, with a link on the Brightspace course page.

• Projects in this course build on each other. Failure to sucessfully complete Project 1 will impede progress on Project 2.
• Steps must be completed in order, e.g., Step v1a must be completed before Step v1b.
• Your code must compile with both g++ and clang. An easy way to verify is with GitHub Codespaces.
• Be sure to follow the good practices we discuss in class
• There are no classes or structs created for this project. You are extracting a set of free functions. Any class you create to solve this problem now would not solve the primary problem of how the srcFacts code uses an XML parser.
• The main() handles XML errors (invalid XML format) with a direct return 1; so the program exits with the status of 1. To exit the program from within any function, use exit(1); which requires the include file stdlib.h.
• While you can create and use other branches, only the work on the main branch counts. The main branch is the default when you git clone and git checkout.
• The code uses the library libarchive to input compressed and archive files, e.g., linux-6.6.xml.gz and demo.xml.zip. To install on Linux, sudo apt-get install libarchive-dev. To install on macOS, brew install libarchive. The GitHub Codespaces image already has libarchive-dev installed.