C Code Quality Metrics
The program qmcalc will read a C source code file from its standard input and print on its standard output a single line containing tens of metrics regarding size, complexity, used keywords, comments and documentation, use of the C preprocessor, and observed formatting style. The full set of the metrics is documented in the file metrics.md.
The code has been written to run efficiently and reliably.
The program receives the code to analyze from its standard input,
so that it can process data coming e.g. directly out of a
git show command,
without having intermediate data touch the disk.
Also, the program can process code
that may not be easy (or possible) to fully parse using a compiler front-end,
due e.g. to missing header files or an unknown compiler configuration.
Furthermore, the software is designed in a way that should allow its easy extension to other languages with C-like syntax, such as Java, C++, C#, and Go. The main thing you need to add is an XMetricsCalculator and an XKeyword class. Pull requests for such extensions are more than welcomed.
- C++ compiler
- GNU make
- CppUnit for running
To build type change the directory to
cd src) and run
This will also generate the files
which can be used for loading the output into other programs
for further processing.
The style checks performed are based on the following guidelines.
- Recommended C Style and Coding Standards - updated version of the Indian Hill C Style and Coding Standards paper
- Wikipedia summary
- The tool is described in detail in the following paper. Diomidis Spinellis, Panos Louridas, and Maria Kechagia. The evolution of C programming practices: A study of the Unix operating system 1973–2015. In Willem Visser and Laurie Williams, editors, ICSE '16: Proceedings of the 38th International Conference on Software Engineering, pages 748–759, New York, May 2016. Association for Computing Machinery. (doi:10.1145/2884781.2884799)
- Some other metrics are based on the paper A Tale of Four Kernels.