# Copyright 2018 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import os
import subprocess

import check_ngcc

cu_checks = [check_ngcc.not_by_gcc]

def check_compile_unit(dso_path, producer, comp_path):
    """check all compiler flags used to build the compile unit.

    Args:
        dso_path: path to the elf/dso
        producer: DW_AT_producer contains the compiler command line.
        comp_path: DW_AT_comp_dir + DW_AT_name

    Returns:
        A set of failed tests.
    """
    failed = set()
    for c in cu_checks:
        if not c(dso_path, producer, comp_path):
            failed.add(c.__module__)

    return failed

def check_compile_units(dso_path):
    """check all compile units in the given dso.

    Args:
        dso_path: path to the dso
    Return:
        True if everything looks fine otherwise False.
    """

    failed = set()
    producer = ''
    comp_path = ''

    readelf = subprocess.Popen(['readelf', '--debug-dump=info',
                                '--dwarf-depth=1', dso_path],
                                stdout=subprocess.PIPE,
                                stderr=open(os.devnull, 'w'))
    for l in readelf.stdout:
        if 'DW_TAG_compile_unit' in l:
            if producer:
                failed = failed.union(check_compile_unit(dso_path, producer,
                                                         comp_path))
            producer = ''
            comp_path = ''
        elif 'DW_AT_producer' in l:
            producer = l
        elif 'DW_AT_name' in l:
            comp_path = os.path.join(comp_path, l.split(':')[-1].strip())
        elif 'DW_AT_comp_dir' in l:
            comp_path = os.path.join(l.split(':')[-1].strip(), comp_path)
    if producer:
        failed = failed.union(check_compile_unit(dso_path, producer, comp_path))

    if failed:
        print('%s failed check: %s' % (dso_path, ' '.join(failed)))
        return False

    return True