Transform C-style comments into C++-style comments preserving Doxygen notation

recomment.py

#!/usr/bin/env python
# Bulk usage:
#   find . -name '*.[ch]pp' -exec bash -c 'recomment.py < "{}" > "{}.out" ; mv "{}.out" "{}"' \;

import sys, re

RE_REPLACE = re.compile(r"(?m)^(\s*?) ?\*(.*)")

def replace_one(match) -> str:
    use_doc = bool(match[1])
    sub = r"\1///\2" if use_doc else r"\1//\2"
    return RE_REPLACE.sub(sub, match[2])

sys.stdout.write(re.sub(r"(?sm)/\*(\**)\s*(.*?)\s*\*/", replace_one, sys.stdin.read()))