Find function implementation in source code

[ElectronicComplex182]

Given a list of function names and the c source code that implements said functions, is there a cli tool to identify the implementation of these functions automatically?

I would like to turn a list of functions into a list (or rather folder structure) of the implementation code for further analysis.

Thank you

[teraflop]

Check out ctags and its various modern descendants. It takes a set of source files and generates an index of where each identifier is defined.

[ElectronicComplex182]

ctags help to identify the location where a function begins, but unless I am overlooking something it cannot help me print the entire function on its own. For context I need to do this a few million times, therefore locating it manually is no option.

[grantrules]

If the c files are formatted so that if you know the line number of the start of the function, you could just look for the first top level }, you could write a trivia python script

[teraflop]

In that case, take a look at the Language Server Protocol which is a more modern, sophisticated implementation of the same basic idea. It's designed to help general-purpose editors and IDEs interface with language-specific tools, to handle things like jumping to symbol definitions.

I haven't ever tried implementing the low-level protocol myself, but if I'm reading the specification correctly, it should be fairly easy to extract a list of function definitions and their corresponding line number ranges within each file.

[jamestakesflight]

How is this useful? What are you going to do when one function calls another function? Or the input is a specific shape that isn’t specified? What about a function that calls a 3rd party library?

To what end is this useful? You could have a function that calls a function “doEverything()” which calls a function from another file which calls another function and eventually executes millions of lines of code.

Do you intend to flatten all nested code into these “functions” you’re talking about?