py_gen/codegen.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.

from collections import defaultdict
import loxi_globals
import struct
import template_utils
import loxi_utils.loxi_utils as utils
import util
import oftype
from loxi_ir import *

modules_by_version = {}

# Map from inheritance root to module name
roots = {
    'of_header': 'message',
    'of_action': 'action',
    'of_oxm': 'oxm',
    'of_instruction': 'instruction',
    'of_meter_band': 'meter_band',
}

# Return the module and class names for the generated Python class
def generate_pyname(ofclass):
    for root, module_name in roots.items():
        if ofclass.name == root:
            return module_name, module_name
        elif ofclass.is_instanceof(root):
            if root == 'of_header':
                # The input files don't prefix message names
                return module_name, ofclass.name[3:]
            else:
                return module_name, ofclass.name[len(root)+1:]
    return 'common', ofclass.name[3:]

# Create intermediate representation, extended from the LOXI IR
def build_ofclasses(version):
    modules = defaultdict(list)
    for ofclass in loxi_globals.ir[version].classes:
        module_name, ofclass.pyname = generate_pyname(ofclass)
        modules[module_name].append(ofclass)
    return modules

def generate_init(out, name, version):
    util.render_template(out, 'init.py', version=version)

def generate_action(out, name, version):
    util.render_template(out, 'module.py',
                         ofclasses=modules_by_version[version]['action'],
                         version=version)

def generate_oxm(out, name, version):
    util.render_template(out, 'module.py',
                         ofclasses=modules_by_version[version]['oxm'],
                         version=version)

def generate_common(out, name, version):
    util.render_template(out, 'module.py',
                         ofclasses=modules_by_version[version]['common'],
                         version=version,
                         extra_template='_common_extra.py')

def generate_const(out, name, version):
    util.render_template(out, 'const.py', version=version,
                         enums=loxi_globals.ir[version].enums)

def generate_instruction(out, name, version):
    util.render_template(out, 'module.py',
                         ofclasses=modules_by_version[version]['instruction'],
                         version=version)

def generate_message(out, name, version):
    util.render_template(out, 'module.py',
                         ofclasses=modules_by_version[version]['message'],
                         version=version,
                         extra_template='_message_extra.py')

def generate_meter_band(out, name, version):
    util.render_template(out, 'module.py',
                         ofclasses=modules_by_version[version]['meter_band'],
                         version=version)

def generate_pp(out, name, version):
    util.render_template(out, 'pp.py')

def generate_util(out, name, version):
    util.render_template(out, 'util.py', version=version)

def init():
    for version in loxi_globals.OFVersions.target_versions:
        modules_by_version[version] = build_ofclasses(version)