blob: 6b0e1ebd55055937c0e57663470abb25f9a89dbe [file] [log] [blame]
Rich Lanea06d0c32013-03-25 08:52:03 -07001# Copyright 2013, Big Switch Networks, Inc.
2#
3# LoxiGen is licensed under the Eclipse Public License, version 1.0 (EPL), with
4# the following special exception:
5#
6# LOXI Exception
7#
8# As a special exception to the terms of the EPL, you may distribute libraries
9# generated by LoxiGen (LoxiGen Libraries) under the terms of your choice, provided
10# that copyright and licensing notices generated by LoxiGen are not altered or removed
11# from the LoxiGen Libraries and the notice provided below is (i) included in
12# the LoxiGen Libraries, if distributed in source code form and (ii) included in any
13# documentation for the LoxiGen Libraries, if distributed in binary form.
14#
15# Notice: "Copyright 2013, Big Switch Networks, Inc. This library was generated by the LoxiGen Compiler."
16#
17# You may not use this file except in compliance with the EPL or LOXI Exception. You may obtain
18# a copy of the EPL at:
19#
20# http://www.eclipse.org/legal/epl-v10.html
21#
22# Unless required by applicable law or agreed to in writing, software
23# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
24# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
25# EPL for the specific language governing permissions and limitations
26# under the EPL.
27
28import pyparsing as P
29
30kw = P.Keyword
31s = P.Suppress
32lit = P.Literal
33
34# Useful for marking the type of a parse result (matches the empty string, but
35# shows up in the result)
36tag = lambda name: P.Empty().setParseAction(P.replaceWith(name))
37
38word = P.Word(P.alphanums + '_')
39
40identifier = word.copy().setName("identifier")
41
42# Type names
43scalar_type = word
44array_type = P.Combine(word + lit('[') - P.Word(P.alphanums + '_') - lit(']'))
45list_type = P.Combine(kw('list') - lit('(') - identifier - lit(')'))
46any_type = (array_type | list_type | scalar_type).setName("type name")
47
48# Structs
49struct_member = P.Group(any_type - identifier - s(';'))
50struct = kw('struct') - identifier - s('{') + \
51 P.Group(P.ZeroOrMore(struct_member)) + \
52 s('}') - s(';')
53
54# Metadata
55metadata_key = P.Or(kw("version")).setName("metadata key")
56metadata = tag('metadata') + s('#') - metadata_key - word
57
58grammar = P.ZeroOrMore(P.Group(struct) | P.Group(metadata))
59grammar.ignore(P.cppStyleComment)
60
61def parse(src):
62 return grammar.parseString(src, parseAll=True)