| # 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. |
| |
| import of_g |
| import loxi_utils.loxi_utils as utils |
| import unittest |
| |
| class OFType(object): |
| """ |
| Encapsulates knowledge about the OpenFlow type system. |
| """ |
| |
| version = None |
| base = None |
| is_array = False |
| array_length = None |
| |
| def __init__(self, string, version): |
| self.version = version |
| self.array_length, self.base = utils.type_dec_to_count_base(string) |
| self.is_array = self.array_length != 1 |
| |
| def gen_init_expr(self): |
| if utils.class_is_list(self.base): |
| v = "[]" |
| elif self.base.find("uint") == 0 or self.base in ["char", "of_port_no_t"]: |
| v = "0" |
| elif self.base == 'of_mac_addr_t': |
| v = '[0,0,0,0,0,0]' |
| elif self.base == 'of_wc_bmap_t': |
| v = 'const.OFPFW_ALL' |
| elif self.base in ['of_octets_t', 'of_port_name_t', 'of_table_name_t', |
| 'of_desc_str_t', 'of_serial_num_t']: |
| v = '""' |
| elif self.base == 'of_match_t': |
| v = 'common.match()' |
| elif self.base == 'of_port_desc_t': |
| v = 'common.port_desc()' |
| else: |
| v = "None" |
| |
| if self.is_array: |
| return "[" + ','.join([v] * self.array_length) + "]" |
| else: |
| return v |
| |
| def gen_pack_expr(self, expr_expr): |
| pack_fmt = self._pack_fmt() |
| if pack_fmt and not self.is_array: |
| return 'struct.pack("!%s", %s)' % (pack_fmt, expr_expr) |
| elif pack_fmt and self.is_array: |
| return 'struct.pack("!%s%s", *%s)' % (self.array_length, pack_fmt, expr_expr) |
| elif self.base == 'of_octets_t': |
| return expr_expr |
| elif utils.class_is_list(self.base): |
| return '"".join([x.pack() for x in %s])' % expr_expr |
| elif self.base == 'of_mac_addr_t': |
| return 'struct.pack("!6B", *%s)' % expr_expr |
| elif self.base in ['of_match_t', 'of_port_desc_t']: |
| return '%s.pack()' % expr_expr |
| elif self.base == 'of_port_name_t': |
| return self._gen_string_pack_expr(16, expr_expr) |
| elif self.base == 'of_table_name_t' or self.base == 'of_serial_num_t': |
| return self._gen_string_pack_expr(32, expr_expr) |
| elif self.base == 'of_desc_str_t': |
| return self._gen_string_pack_expr(256, expr_expr) |
| else: |
| return "'TODO pack %s'" % self.base |
| |
| def _gen_string_pack_expr(self, length, expr_expr): |
| return 'struct.pack("!%ds", %s)' % (length, expr_expr) |
| |
| def gen_unpack_expr(self, buf_expr, offset_expr): |
| pack_fmt = self._pack_fmt() |
| if pack_fmt and not self.is_array: |
| return "struct.unpack_from('!%s', %s, %s)[0]" % (pack_fmt, buf_expr, offset_expr) |
| elif pack_fmt and self.is_array: |
| return "list(struct.unpack_from('!%d%s', %s, %s))" % (self.array_length, pack_fmt, buf_expr, offset_expr) |
| elif self.base == 'of_octets_t': |
| return "%s[%s:]" % (buf_expr, offset_expr) |
| elif self.base == 'of_mac_addr_t': |
| return "list(struct.unpack_from('!6B', %s, %s))" % (buf_expr, offset_expr) |
| elif self.base == 'of_match_t': |
| return 'common.match.unpack(buffer(%s, %s))' % (buf_expr, offset_expr) |
| elif self.base == 'of_port_desc_t': |
| return 'common.port_desc.unpack(buffer(%s, %s))' % (buf_expr, offset_expr) |
| elif self.base == 'of_list_action_t': |
| return 'action.unpack_list(buffer(%s, %s))' % (buf_expr, offset_expr) |
| elif self.base == 'of_list_flow_stats_entry_t': |
| return 'common.unpack_list_flow_stats_entry(buffer(%s, %s))' % (buf_expr, offset_expr) |
| elif self.base == 'of_list_queue_prop_t': |
| return 'common.unpack_list_queue_prop(buffer(%s, %s))' % (buf_expr, offset_expr) |
| elif self.base == 'of_list_packet_queue_t': |
| return 'common.unpack_list_packet_queue(buffer(%s, %s))' % (buf_expr, offset_expr) |
| elif self.base == 'of_port_name_t': |
| return self._gen_string_unpack_expr(16, buf_expr, offset_expr) |
| elif self.base == 'of_table_name_t' or self.base == 'of_serial_num_t': |
| return self._gen_string_unpack_expr(32, buf_expr, offset_expr) |
| elif self.base == 'of_desc_str_t': |
| return self._gen_string_unpack_expr(256, buf_expr, offset_expr) |
| elif utils.class_is_list(self.base): |
| element_cls = utils.list_to_entry_type(self.base)[:-2] |
| if ((element_cls, self.version) in of_g.is_fixed_length): |
| klass_name = self.base[8:-2] |
| element_size, = of_g.base_length[(element_cls, self.version)], |
| return 'util.unpack_array(common.%s.unpack, %d, buffer(%s, %s))' % (klass_name, element_size, buf_expr, offset_expr) |
| else: |
| return "None # TODO unpack list %s" % self.base |
| else: |
| return "None # TODO unpack %s" % self.base |
| |
| def _gen_string_unpack_expr(self, length, buf_expr, offset_expr): |
| return 'str(buffer(%s, %s, %d)).rstrip("\\x00")' % (buf_expr, offset_expr, length) |
| |
| def _pack_fmt(self): |
| if self.base == "char": |
| return "B" |
| if self.base == "uint8_t": |
| return "B" |
| if self.base == "uint16_t": |
| return "H" |
| if self.base == "uint32_t": |
| return "L" |
| if self.base == "uint64_t": |
| return "Q" |
| if self.base == "of_port_no_t": |
| if self.version == of_g.VERSION_1_0: |
| return "H" |
| else: |
| return "L" |
| if self.base == "of_fm_cmd_t": |
| if self.version == of_g.VERSION_1_0: |
| return "H" |
| else: |
| return "B" |
| if self.base in ["of_wc_bmap_t", "of_match_bmap_t"]: |
| if self.version in [of_g.VERSION_1_0, of_g.VERSION_1_1]: |
| return "L" |
| else: |
| return "Q" |
| return None |
| |
| class TestOFType(unittest.TestCase): |
| def test_init(self): |
| from oftype import OFType |
| self.assertEquals("None", OFType("of_list_action_t", 1).gen_init_expr()) |
| self.assertEquals("[0,0,0]", OFType("uint32_t[3]", 1).gen_init_expr()) |
| |
| def test_pack(self): |
| self.assertEquals('struct.pack("!16s", "foo")', OFType("of_port_name_t", 1).gen_pack_expr('"foo"')) |
| |
| def test_unpack(self): |
| self.assertEquals('str(buffer(buf, 8, 16)).rstrip("\\x00")', OFType("of_port_name_t", 1).gen_unpack_expr('buf', 8)) |
| |
| if __name__ == '__main__': |
| unittest.main() |