Ever wonder which ifdef matches which endif and how those ifdef/endif pairs nest each other? If you have an advanced IDE, that won't be a problem. But in many cases, we only have text editor with basic syntax highlight. annotate_ifdef is a utility to help understand the ifdef/endif hierarchy.

annotate_ifdef reads file content, adds annotation to line heads, and prints lines to standard output. At the end, it reports whether all ifdef are closed by endif and whether there are redundant endif.

Two command line arguments are expected.

annotate_ifdef <language> <filename>

language should be one of C/makepp/Verilog. It's case insensitive.

Assume example.h has the content as follows.

#ifdef A
#define B 5
#if C==2
#define D
#endif
#endif

Run command annotate_ifdef c example.h. The output is like this.

$ annotate_ifdef c example.h
Checking example.h c.
r       1       :#ifdef A
|       2       :#define B 5
|r      3       :#if C==2
||      4       :#define D
|L      5       :#endif
L       6       :#endif
        7       :
PASS