#!/usr/bin/env python3
#
# Copyright 2016 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Archive all source files that are references in binary debug info.

Invoked by libfuzzer buildbots. Executes dwarfdump to parse debug info.
"""

from __future__ import print_function

import argparse
import os
import re
import subprocess
import zipfile

compile_unit_re = re.compile('.*DW_TAG_compile_unit.*')
at_name_re = re.compile('.*DW_AT_name.*"(.*)".*')


def main():
  parser = argparse.ArgumentParser(description='Zip binary sources.')
  parser.add_argument('--binary', required=True, help='binary file to read')
  parser.add_argument('--workdir',
                      required=True,
                      help='working directory to use to resolve relative paths')
  parser.add_argument(
      '--srcdir',
      required=True,
      help='sources root directory to calculate zip entry names')
  parser.add_argument('--output', required=True, help='output zip file name')
  parser.add_argument('--dwarfdump',
                      required=False,
                      default='dwarfdump',
                      help='path to dwarfdump utility')
  args = parser.parse_args()

  # Dump .debug_info section.
  out = subprocess.check_output([args.dwarfdump, '-i', args.binary])

  looking_for_unit = True
  compile_units = set()

  # Look for DW_AT_name within DW_TAG_compile_unit
  for line in out.splitlines():
    if looking_for_unit and compile_unit_re.match(line):
      looking_for_unit = False
    elif not looking_for_unit:
      match = at_name_re.match(line)
      if match:
        compile_units.add(match.group(1))
        looking_for_unit = True

  # Zip sources.
  with zipfile.ZipFile(args.output, 'w') as z:
    for compile_unit in sorted(compile_units):
      src_file = os.path.abspath(os.path.join(args.workdir, compile_unit))
      print(src_file)
      z.write(src_file, os.path.relpath(src_file, args.srcdir))


if __name__ == '__main__':
  main()