/callgraph-explorer

Primary LanguagePython

README

This is (will be) a tool to build a callgraph from a number of source files. It relies heavily on other python libraries (pycparser, ast) to do the heavy-lifting related to parsing the code.

We will start targeting C (using pycparser to get the AST) but keeping in mind that we would like also to deal with Python.

Design

These are the steps.

  1. Get the AST of every compilation unit.

    For C:

    1. Preprocess compilation unit. This requires setting up all necessary -Ds, include paths, and also clearing all the non-standard stuff (e.g. __attribute__ for GCC). For the include paths, remember to use the mock of libc that comes included in the pycparser repo.

      NOTE: preprocessing the files so that pycparser does not choke on them is usually the most tedious part.

    2. Run pycparser and get the AST.

    For Python:

    1. Read in memory the content of the source file. Then parse it using the facilities contained in the ast module of the standard library.

  2. Exctract the function definition/function call information of every module/compilation unit. Notice that the name of the function is not enough to determine exactly the function, also the name of the compilation unit is necessary (e.g., for the main() function).

  3. Simulate the linking phase. For C, one needs to specify which files are linked together. For python: TODO

TODO and to understand

It is not yet clear how to exactly do things for python.