pydis.py

#!/bin/env python

import py_compile
import argparse
import os
import time
import marshal
import dis

parser = argparse.ArgumentParser(
    prog="Python compilation artefacts explorer",
    description="Compiles, disassembles and binary-views python source code.",
    epilog="""Needs xxd installed. Use like this: 1) compile source file to pyc
  compiled python code, 2) disassemble the binary to hexcode as used by python interpreter.""",
)

parser.add_argument("-c", "--compile")
parser.add_argument("-d", "--disassemble")
args = parser.parse_args()


def compile_file(target):
    """Compiles python source file to hexcode binary."""
    fname = os.path.join(
        os.path.dirname(target), os.path.splitext(os.path.basename(target))[0]
    )
    obj_name = f"{fname}.pyc"
    t_start = time.perf_counter()
    py_compile.compile(target, obj_name)
    t_stop = time.perf_counter()
    msg = f"Compiled {target} to {obj_name} in {t_stop-t_start:.4f} seconds."
    print(msg)


def view_pyc_file(target):
    """Reads compiled python file and disassembles to hex code as used by
    interpreter"""
    with open(target, "rb") as file:
        file.seek(16)
        code = marshal.load(file)
        dis.disassemble(code)


if __name__ == "__main__":
    if args.compile:
        compile_file(args.compile)
    elif args.disassemble:
        view_pyc_file(args.disassemble)