py_gen/util.py

# Copyright 2013, Big Switch Networks, Inc.
#
# LoxiGen is licensed under the Eclipse Public License, version 1.0 (EPL), with
# the following special exception:
#
# LOXI Exception
#
# As a special exception to the terms of the EPL, you may distribute libraries
# generated by LoxiGen (LoxiGen Libraries) under the terms of your choice, provided
# that copyright and licensing notices generated by LoxiGen are not altered or removed
# from the LoxiGen Libraries and the notice provided below is (i) included in
# the LoxiGen Libraries, if distributed in source code form and (ii) included in any
# documentation for the LoxiGen Libraries, if distributed in binary form.
#
# Notice: "Copyright 2013, Big Switch Networks, Inc. This library was generated by the LoxiGen Compiler."
#
# You may not use this file except in compliance with the EPL or LOXI Exception. You may obtain
# a copy of the EPL at:
#
# http://www.eclipse.org/legal/epl-v10.html
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# EPL for the specific language governing permissions and limitations
# under the EPL.

"""
Utilities for generating the target Python code
"""

import os
import of_g
import loxi_front_end.type_maps as type_maps
import loxi_utils.loxi_utils as utils

templates_dir = os.path.join(os.path.dirname(os.path.realpath(__file__)), 'templates')

def render_template(out, name, **context):
    utils.render_template(out, name, [templates_dir], context)

def render_static(out, name):
    utils.render_static(out, name, [templates_dir])

def lookup_unified_class(cls, version):
    unified_class = of_g.unified[cls][version]
    if "use_version" in unified_class: # deref version ref
        ref_version = unified_class["use_version"]
        unified_class = of_g.unified[cls][ref_version]
    return unified_class

def primary_wire_type(cls, version):
    if cls in type_maps.stats_reply_list:
        return type_maps.type_val[("of_stats_reply", version)]
    elif cls in type_maps.stats_request_list:
        return type_maps.type_val[("of_stats_request", version)]
    elif cls in type_maps.flow_mod_list:
        return type_maps.type_val[("of_flow_mod", version)]
    elif (cls, version) in type_maps.type_val:
        return type_maps.type_val[(cls, version)]
    elif type_maps.message_is_extension(cls, version):
        return type_maps.type_val[("of_experimenter", version)]
    elif type_maps.action_is_extension(cls, version):
        return type_maps.type_val[("of_action_experimenter", version)]
    elif type_maps.action_id_is_extension(cls, version):
        return type_maps.type_val[("of_action_id_experimenter", version)]
    elif type_maps.instruction_is_extension(cls, version):
        return type_maps.type_val[("of_instruction_experimenter", version)]
    elif type_maps.queue_prop_is_extension(cls, version):
        return type_maps.type_val[("of_queue_prop_experimenter", version)]
    elif type_maps.table_feature_prop_is_extension(cls, version):
        return type_maps.type_val[("of_table_feature_prop_experimenter", version)]
    else:
        raise ValueError("No wiretype for %s in version %d" % (cls, version))

def constant_for_value(version, group, value):
    return (["const." + v["ofp_name"] for k, v in of_g.identifiers.items()
             if k in of_g.identifiers_by_group[group] and
                v["values_by_version"].get(version, None) == value] or [value])[0]