#
# gdb helper commands and functions for Linux kernel debugging
#
#  common utilities
#
# Copyright (c) Siemens AG, 2011-2013
#
# Authors:
#  Jan Kiszka <jan.kiszka@siemens.com>
#
# This work is licensed under the terms of the GNU GPL version 2.
#

import gdb


class CachedType:
    def __init__(self, name):
        self._type = None
        self._name = name

    def _new_objfile_handler(self, event):
        self._type = None
        gdb.events.new_objfile.disconnect(self._new_objfile_handler)

    def get_type(self):
        if self._type is None:
            self._type = gdb.lookup_type(self._name)
            if self._type is None:
                raise gdb.GdbError(
                    "cannot resolve type '{0}'".format(self._name))
            if hasattr(gdb, 'events') and hasattr(gdb.events, 'new_objfile'):
                gdb.events.new_objfile.connect(self._new_objfile_handler)
        return self._type