tests/scripts/thread-cert/pktverify/utils.py

#!/usr/bin/env python3
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import logging
import os
import sys
from typing import Callable, Union

from pktverify.addrs import EthAddr, ExtAddr, Ipv6Addr
from pktverify.bytes import Bytes
from pktverify.null_field import nullField


def make_filter_func(func: Union[str, Callable], **vars) -> Callable:
    """
    Convert the filter to a callable function if it's a string.

    :param func: The filter string or callable.
    :param vars: The variables.
    :return: The filter callable.
    """
    if isinstance(func, str):
        # if func is a string, compile it to a function
        func = func.format_map({k: repr(v) for k, v in vars.items()}).strip()
        print("\t%s" % func, file=sys.stderr)
        code = compile('(\n' + func + '\n)', func, "eval")

        def func(p):
            return eval(
                code, None, {
                    'p': p,
                    'coap': p.coap,
                    'wpan': p.wpan,
                    'mle': p.mle,
                    'ipv6': p.ipv6,
                    'lowpan': p.lowpan,
                    'eth': p.eth,
                    'icmpv6': p.icmpv6,
                    'udp': p.udp,
                    'thread_bl': p.thread_bl,
                    'thread_meshcop': p.thread_meshcop,
                    'Bytes': Bytes,
                    'ExtAddr': ExtAddr,
                    'Ipv6Addr': Ipv6Addr,
                    'EthAddr': EthAddr,
                    'thread_nm': p.thread_nm,
                    'thread_nwd': p.thread_nwd,
                    'thread_address': p.thread_address,
                    'thread_bcn': p.thread_bcn,
                    'dns': p.dns,
                    'null': nullField,
                })
    else:
        assert not vars, 'can not provide vars for non-str filter: %r %r' % (func, vars)

    assert callable(func)
    return func


def _setup_wireshark_disabled_protos():
    home = os.environ['HOME']
    wireshark_config_dir = os.path.join(home, '.config', 'wireshark')
    os.makedirs(wireshark_config_dir, exist_ok=True)
    disabled_protos_path = os.path.join(wireshark_config_dir, 'disabled_protos')
    # read current disabled protos
    try:
        with open(disabled_protos_path, 'rt') as fd:
            disabled_protos = set(l.strip() for l in fd if l.strip() != '')
    except FileNotFoundError:
        disabled_protos = set()

    old_disabled_protos_num = len(disabled_protos)
    disabled_protos.add('lwm')
    disabled_protos.add('prp')
    disabled_protos.add('stcsig')
    disabled_protos.add('transum')
    disabled_protos.add('zbee_nwk')
    disabled_protos.add('zbee_nwk_gp')

    if len(disabled_protos) > old_disabled_protos_num:
        logging.info(f"set disabled_protos = {' '.join(disabled_protos)}")
        with open(disabled_protos_path, 'wt') as fd:
            fd.write('\n'.join(sorted(disabled_protos)))
            fd.write('\n')


def get_wireshark_dir() -> str:
    """
    :return: The path to wireshark directory.
    """
    dir = '/tmp/thread-wireshark'
    _setup_wireshark_disabled_protos()
    return dir


def which_tshark() -> str:
    """
    :return: The path to `tshark` executable.
    """
    return os.path.join(get_wireshark_dir(), 'tshark')


def which_dumpcap() -> str:
    """
    :return: The path to `dumpcap` executable.
    """
    return os.path.join(get_wireshark_dir(), 'dumpcap')


def which_mergecap() -> str:
    """
    :return: The path to `mergecap` executable.
    """
    return os.path.join(get_wireshark_dir(), 'mergecap')


def colon_hex(hexstr, interval) -> str:
    """ Convert hexstr to colon seperated string every interval

    :param hexstr: The hex string to convert.
    :param interval: The interval number.
    :return: The colon seperated string.
    """
    assert len(hexstr) % interval == 0
    return ':'.join(hexstr[i:i + interval] for i in range(0, len(hexstr), interval))


def is_sublist(lst1: list, lst2: list) -> bool:
    """ Test whether lst1 is a slice of lst2

    :param lst1: The list to judge if it is a sublist of lst2.
    :param lst2: The list to judge if contains lst1.
    :return: Whether lst1 is a slice of lst2.
    """
    return lst1 in [lst2[i:len(lst1) + i] for i in range(len(lst1))]