Code Spelunking: Exploring Cavernous Code Bases

ABSTRACT

Try to remember your first day at your first software job. Do you recall what you were asked to do, after the human resources people were done with you? Were you asked to write a piece of fresh code? Probably not. It is far more likely that you were asked to fix a bug, or several, and to try to understand a large, poorly documented collection of source code.

Of course, this doesn't just happen to new graduates; it happens to all of us whenever we start a new job or look at a new piece of code. With experience we all develop a set of techniques for working with large, unfamiliar source bases. This is what I call code spelunking.

Code spelunking is very different from other engineering practices because it is done long after the initial design and implementation of a system. It is a set of forensic techniques used after the crime has been committed.

There are several questions that code spelunkers need to ask, and tools are available to help them answer these questions. I will look at some of these tools, addressing their shortcomings and pointing out possible improvements.

INDEX TERMS

Primary Classification:
  K. Computing Milieux
  K.6 MANAGEMENT OF COMPUTING AND INFORMATION SYSTEMS
      K.6.3 Software Management
          Subjects: Software maintenance

Additional Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.2 Design Tools and Techniques
          Subjects: Computer-aided software engineering (CASE)

  K. Computing Milieux
  K.6 MANAGEMENT OF COMPUTING AND INFORMATION SYSTEMS
      K.6.3 Software Management
          Subjects: Software process; Software development

General Terms:
Design, Human Factors, Management, Standardization