px4-firmware/Tools/msg/px_generate_uorb_compressed...

233 lines
9.2 KiB
Python
Executable File

#!/usr/bin/env python3
#############################################################################
#
# Copyright (C) 2023 PX4 Pro Development Team. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
# 3. Neither the name PX4 nor the names of its contributors may be
# used to endorse or promote products derived from this software
# without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
#############################################################################
"""
Generates cpp source + header files with compressed uorb topic fields from json files
"""
import argparse
import json
import struct
from operator import itemgetter
import sys
import os
sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), '../../src/lib/heatshrink'))
import heatshrink_encode
def parse_json_files(json_files: [str]) -> dict:
"""Read list of json files into a dict"""
definitions = {}
for json_file in json_files:
with open(json_file, encoding='utf-8') as file_handle:
definition = json.load(file_handle)
assert definition['name'] not in definitions
definitions[definition['name']] = definition
definitions[definition['name']]['completed'] = False
return definitions
def get_ordered_list_by_dependency(name: str, definitions: dict) -> [str]:
"""Iterate dependency graph and create an ordered list"""
if definitions[name]['completed']:
return []
ret = []
# Get nested types first (DFS)
for dependency in definitions[name]['dependencies']:
ret.extend(get_ordered_list_by_dependency(dependency, definitions))
ret.append(name)
definitions[name]['completed'] = True
return ret
def get_field_definitions(names: [str], definitions: dict) -> (bytes, [str]):
"""Get byte array with all definitions"""
ret = bytes()
formats_list = []
for name in names:
# Format as '<# orb_ids><orb_id0...><# orb_ids dependencies<orb_id_dependency0...><fields><null>'
assert len(definitions[name]['orb_ids']) < 255
assert len(definitions[name]['dependencies']) < 255
ret += struct.pack('<B', len(definitions[name]['orb_ids']))
for orb_id in definitions[name]['orb_ids']:
assert orb_id < (1 << 16)
ret += struct.pack('<H', orb_id)
# Dependencies
ret += struct.pack('<B', len(definitions[name]['dependencies']))
for dependent_message_name in definitions[name]['dependencies']:
# Get ORB ID by looking up the name in all definitions
dependent_orb_id_list = [definitions[k]['main_orb_id'] for k in definitions if
definitions[k]['name'] == dependent_message_name]
assert len(dependent_orb_id_list) == 1
orb_id = dependent_orb_id_list[0]
assert (1 << 16) > orb_id >= 0
ret += struct.pack('<H', orb_id)
ret += bytes(definitions[name]['fields'], 'latin1')
ret += b'\0'
formats_list.append(definitions[name]['fields'])
return ret, formats_list
def write_fields_to_cpp_file(file_name: str, compressed_fields: bytes):
fields_str = ', '.join(str(c) for c in compressed_fields)
with open(file_name, 'w') as file_handle:
file_handle.write('''
// Auto-generated from px4_generate_uorb_compressed_fields.py
#include <uORB/topics/uORBMessageFieldsGenerated.hpp>
namespace uORB {
static const uint8_t compressed_fields[] = {
{FIELDS}
};
const uint8_t* orb_compressed_message_formats()
{
return compressed_fields;
}
unsigned orb_compressed_message_formats_size()
{
return sizeof(compressed_fields) / sizeof(compressed_fields[0]);
}
} // namespace uORB
'''.replace('{FIELDS}', fields_str))
def c_encode(s, encoding='ascii'):
result = ''
for c in s:
if not (32 <= ord(c) < 127) or c in ('\\', '"'):
result += '\\%03o' % ord(c)
else:
result += c
return '"' + result + '"'
def write_fields_to_hpp_file(file_name: str, definitions: dict, window_length: int, lookahead_length: int,
format_list: [str]):
max_tokenized_field_length, max_tokenized_field_length_msg = max(
((len(definitions[k]['fields']), k) for k in definitions), key=itemgetter(0))
max_num_orb_ids = max(len(definitions[k]['orb_ids']) for k in definitions)
max_num_orb_id_dependencies = max(len(definitions[k]['dependencies']) for k in definitions)
with open(file_name, 'w') as file_handle:
file_handle.write('''
// Auto-generated from px4_generate_uorb_compressed_fields.py
#include <cstdint>
namespace uORB {
/**
* Get compressed string of all uorb message format definitions
*/
const uint8_t* orb_compressed_message_formats();
/**
* Get length of compressed message format definitions
*/
unsigned orb_compressed_message_formats_size();
static constexpr unsigned orb_tokenized_fields_max_length = {MAX_TOKENIZED_FIELD_LENGTH}; // {MAX_TOKENIZED_FIELD_LENGTH_MSG}
static constexpr unsigned orb_compressed_max_num_orb_ids = {MAX_NUM_ORB_IDS};
static constexpr unsigned orb_compressed_max_num_orb_id_dependencies = {MAX_NUM_ORB_ID_DEPENDENCIES};
static constexpr unsigned orb_compressed_heatshrink_window_length = {WINDOW_LENGTH};
static constexpr unsigned orb_compressed_heatshrink_lookahead_length = {LOOKAHEAD_LENGTH};
#define ORB_DECOMPRESSED_MESSAGE_FIELDS {{DECOMPRESSED_MESSAGE_FIELDS}}
} // namespace uORB
'''
.replace('{MAX_TOKENIZED_FIELD_LENGTH}', str(max_tokenized_field_length))
.replace('{MAX_TOKENIZED_FIELD_LENGTH_MSG}', max_tokenized_field_length_msg)
.replace('{MAX_NUM_ORB_IDS}', str(max_num_orb_ids))
.replace('{MAX_NUM_ORB_ID_DEPENDENCIES}', str(max_num_orb_id_dependencies))
.replace('{WINDOW_LENGTH}', str(window_length))
.replace('{LOOKAHEAD_LENGTH}', str(lookahead_length))
.replace('{DECOMPRESSED_MESSAGE_FIELDS}', ','.join(c_encode(x) for x in format_list))
)
def main():
parser = argparse.ArgumentParser(description='Generate compressed uorb topic fields')
parser.add_argument('-f', dest='file',
help="json input files",
nargs="+")
parser.add_argument('--source-output-file', dest='output_cpp',
help='cpp output file to generate')
parser.add_argument('--header-output-file', dest='output_hpp',
help='hpp output file to generate')
parser.add_argument('-v', '--verbose',
action='store_true',
help="verbose output")
args = parser.parse_args()
if args.file is not None:
definitions = parse_json_files(args.file)
# Get array of all field definitions
names = []
for definition in definitions:
names.extend(get_ordered_list_by_dependency(definitions[definition]['name'], definitions))
names.reverse() # Dependent definitions must be after
assert len(names) == len(definitions)
for definition in definitions: # sanity check
assert definitions[definition]['completed']
field_definitions, format_list = get_field_definitions(names, definitions)
# Compress
window_size = 8 # Larger value = better compression; memory requirement (for decompression): 2 ^ window_size
lookahead = 4
compressed_field_definitions = heatshrink_encode.encode(field_definitions, window_size, lookahead)
if args.verbose:
print(
f'Field definitions: size: {len(field_definitions)}, reduction from compression: {len(field_definitions) - len(compressed_field_definitions)}')
# Write cpp & hpp file
write_fields_to_cpp_file(args.output_cpp, compressed_field_definitions)
write_fields_to_hpp_file(args.output_hpp, definitions, window_size, lookahead, format_list)
if __name__ == "__main__":
main()