elftools/common/utils.py

#-------------------------------------------------------------------------------
# elftools: common/utils.py
#
# Miscellaneous utilities for elftools
#
# Eli Bendersky (eliben@gmail.com)
# This code is in the public domain
#-------------------------------------------------------------------------------
from .exceptions import ELFParseError, ELFError
from ..construct import ConstructError


def struct_parse(struct, stream, stream_pos=None):
    """ Convenience function for using the given struct to parse a stream.
        If stream_pos is provided, the stream is seeked to this position before
        the parsing is done. Otherwise, the current position of the stream is
        used.
        Wraps the error thrown by construct with ELFParseError.
    """
    try:
        if stream_pos is not None:
            stream.seek(stream_pos)
        return struct.parse_stream(stream)
    except ConstructError as e:
        raise ELFParseError(e.message)
    

def elf_assert(cond, msg=''):
    """ Assert that cond is True, otherwise raise ELFError(msg)
    """
    if not cond:
        raise ELFError(msg)