uorb: compress format definitions

Reduces flash usage by ~16KB.

- compress formats at build-time into a single string with all formats
- then at runtime iteratively decompress using
  https://github.com/atomicobject/heatshrink

Tools/astyle/files_to_check_code_style.sh

@@ -25,6 +25,7 @@ exec find boards msg src platforms test \
     -path src/lib/crypto/monocypher -prune -o \
     -path src/lib/crypto/libtomcrypt -prune -o \
     -path src/lib/crypto/libtommath -prune -o \
+    -path src/lib/heatshrink/heatshrink -prune -o \
     -path src/modules/uxrce_dds_client/Micro-XRCE-DDS-Client -prune -o \
     -path src/lib/cdrstream/cyclonedds -prune -o \
     -path src/lib/cdrstream/rosidl -prune -o \

Tools/msg/px_generate_uorb_compressed_fields.py

@@ -0,0 +1,232 @@
+#!/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()

Tools/msg/px_generate_uorb_topic_files.py

@@ -70,9 +70,8 @@ __license__ = "BSD"
 __email__ = "thomasgubler@gmail.com"
 
 
-TEMPLATE_FILE = ['msg.h.em', 'msg.cpp.em', 'uorb_idl_header.h.em']
-TOPICS_LIST_TEMPLATE_FILE = ['uORBTopics.hpp.em', 'uORBTopics.cpp.em']
-OUTPUT_FILE_EXT = ['.h', '.cpp', '.h']
+TEMPLATE_FILE = ['msg.h.em', 'msg.cpp.em', 'uorb_idl_header.h.em', 'msg.json.em']
+TOPICS_LIST_TEMPLATE_FILE = ['uORBTopics.hpp.em', 'uORBTopics.cpp.em', None, None]
 INCL_DEFAULT = ['std_msgs:./msg/std_msgs']
 PACKAGE = 'px4'
 TOPICS_TOKEN = '# TOPICS '
@@ -105,7 +104,7 @@ def get_topics(filename):
     return result
 
 
-def generate_output_from_file(format_idx, filename, outputdir, package, templatedir, includepath):
+def generate_output_from_file(format_idx, filename, outputdir, package, templatedir, includepath, all_topics):
     """
     Converts a single .msg file to an uorb header/source file
     """
@@ -155,6 +154,7 @@ def generate_output_from_file(format_idx, filename, outputdir, package, template
         "msg_context": msg_context,
         "spec": spec,
         "topics": topics,
+        "all_topics": all_topics,
     }
 
     # Make sure output directory exists:
@@ -162,10 +162,11 @@ def generate_output_from_file(format_idx, filename, outputdir, package, template
         os.makedirs(outputdir)
 
     template_file = os.path.join(templatedir, TEMPLATE_FILE[format_idx])
+    extension = os.path.splitext(os.path.splitext(TEMPLATE_FILE[format_idx])[0])[1]
     if format_idx == 2:
-        output_file = os.path.join(outputdir, file_base_name + OUTPUT_FILE_EXT[format_idx])
+        output_file = os.path.join(outputdir, file_base_name + extension)
     else:
-        output_file = os.path.join(outputdir, full_type_name_snake + OUTPUT_FILE_EXT[format_idx])
+        output_file = os.path.join(outputdir, full_type_name_snake + extension)
 
     return generate_by_template(output_file, template_file, em_globals)
 
@@ -195,17 +196,13 @@ def generate_by_template(output_file, template_file, em_globals):
     return True
 
 
-def generate_topics_list_file_from_files(files, outputdir, template_filename, templatedir):
+def generate_topics_list_file_from_files(files, outputdir, template_filename, templatedir, all_topics):
     # generate cpp file with topics list
     filenames = []
     for filename in [os.path.basename(p) for p in files if os.path.basename(p).endswith(".msg")]:
         filenames.append(re.sub(r'(?<!^)(?=[A-Z])', '_', filename).lower())
 
-    topics = []
-    for msg_filename in files:
-        topics.extend(get_topics(msg_filename))
-
-    tl_globals = {"msgs": filenames, "topics": topics}
+    tl_globals = {"msgs": filenames, "all_topics": all_topics}
     tl_template_file = os.path.join(templatedir, template_filename)
     tl_out_file = os.path.join(outputdir, template_filename.replace(".em", ""))
 
@@ -222,8 +219,9 @@ if __name__ == "__main__":
     parser.add_argument('--headers', help='Generate header files', action='store_true')
     parser.add_argument('--sources', help='Generate source files', action='store_true')
     parser.add_argument('--uorb-idl-header', help='Generate uORB compatible idl header', action='store_true')
+    parser.add_argument('--json', help='Generate json files', action='store_true')
     parser.add_argument('-f', dest='file',
-                        help="files to convert (use only without -d)",
+                        help="files to convert",
                         nargs="+")
     parser.add_argument('-i', dest="include_paths",
                         help='Additional Include Paths', nargs="*",
@@ -247,17 +245,21 @@ if __name__ == "__main__":
     elif args.sources:
         generate_idx = 1
     elif args.uorb_idl_header:
-        for f in args.file:
-            print(f)
-            generate_output_from_file(2, f, args.outputdir, args.package, args.templatedir, INCL_DEFAULT)
-        exit(0)
+        generate_idx = 2
+    elif args.json:
+        generate_idx = 3
     else:
-        print('Error: either --headers or --sources must be specified')
+        print('Error: either --headers, --sources or --json must be specified')
         exit(-1)
     if args.file is not None:
+        all_topics = []
+        for msg_filename in args.file:
+            all_topics.extend(get_topics(msg_filename))
+        all_topics.sort()
+
         for f in args.file:
-            generate_output_from_file(generate_idx, f, args.outputdir, args.package, args.templatedir, INCL_DEFAULT)
+            generate_output_from_file(generate_idx, f, args.outputdir, args.package, args.templatedir, INCL_DEFAULT, all_topics)
 
         # Generate topics list header and source file
-        if os.path.isfile(os.path.join(args.templatedir, TOPICS_LIST_TEMPLATE_FILE[generate_idx])):
-            generate_topics_list_file_from_files(args.file, args.outputdir, TOPICS_LIST_TEMPLATE_FILE[generate_idx], args.templatedir)
+        if TOPICS_LIST_TEMPLATE_FILE[generate_idx] is not None and os.path.isfile(os.path.join(args.templatedir, TOPICS_LIST_TEMPLATE_FILE[generate_idx])):
+            generate_topics_list_file_from_files(args.file, args.outputdir, TOPICS_LIST_TEMPLATE_FILE[generate_idx], args.templatedir, all_topics)

Tools/msg/templates/uorb/msg.cpp.em

@@ -14,6 +14,7 @@
 @#  - spec (msggen.MsgSpec) Parsed specification of the .msg file
 @#  - search_path (dict) search paths for genmsg
 @#  - topics (List of String) topic names
+@#  - all_topics (List of String) all generated topic names (sorted)
 @###############################################
 /****************************************************************************
  *
@@ -59,7 +60,6 @@ uorb_struct = '%s_s'%name_snake_case
 
 sorted_fields = sorted(spec.parsed_fields(), key=sizeof_field_type, reverse=True)
 struct_size, padding_end_size = add_padding_bytes(sorted_fields, search_path)
-topic_fields = ["%s %s" % (convert_type(field.type, True), field.name) for field in sorted_fields]
 }@
 
 #include <inttypes.h>
@@ -72,12 +72,9 @@ topic_fields = ["%s %s" % (convert_type(field.type, True), field.name) for field
 #include <lib/matrix/matrix/math.hpp>
 #include <lib/mathlib/mathlib.h>
 
-@# join all msg files in one line e.g: "float[3] position;float[3] velocity;bool armed"
-@# This is used for the logger
-constexpr char __orb_@(name_snake_case)_fields[] = "@( ";".join(topic_fields) );";
-
 @[for topic in topics]@
-ORB_DEFINE(@topic, struct @uorb_struct, @(struct_size-padding_end_size), __orb_@(name_snake_case)_fields, static_cast<orb_id_size_t>(ORB_ID::@topic));
+static_assert(static_cast<orb_id_size_t>(ORB_ID::@topic) == @(all_topics.index(topic)), "ORB_ID index mismatch");
+ORB_DEFINE(@topic, struct @uorb_struct, @(struct_size-padding_end_size), static_cast<orb_id_size_t>(ORB_ID::@topic));
 @[end for]
 
 void print_message(const orb_metadata *meta, const @uorb_struct& message)

Tools/msg/templates/uorb/msg.json.em

@@ -0,0 +1,49 @@
+@###############################################
+@#
+@# PX4 ROS compatible message source code
+@# generation for C++
+@#
+@# EmPy template for generating <msg>.h files
+@# Based on the original template for ROS
+@#
+@###############################################
+@# Start of Template
+@#
+@# Context:
+@#  - file_name_in (String) Source file
+@#  - spec (msggen.MsgSpec) Parsed specification of the .msg file
+@#  - search_path (dict) search paths for genmsg
+@#  - topics (List of String) topic names
+@#  - all_topics (List of String) all generated topic names (sorted)
+@###############################################
+
+@{
+import genmsg.msgs
+import json
+
+from px_generate_uorb_topic_helper import * # this is in Tools/
+
+uorb_struct = '%s_s'%name_snake_case
+
+sorted_fields = sorted(spec.parsed_fields(), key=sizeof_field_type, reverse=True)
+struct_size, padding_end_size = add_padding_bytes(sorted_fields, search_path)
+topic_fields = ["%s %s" % (convert_type(field.type, True), field.name) for field in sorted_fields]
+
+dependencies = []
+for field in spec.parsed_fields():
+    if not field.is_header:
+        type_name = field.type
+        # detect embedded types
+        sl_pos = type_name.find('/')
+        if sl_pos >= 0: # nested type
+            dependencies.append(field.base_type)
+}@
+
+{
+@# join all msg files in one line e.g: "float[3] position;float[3] velocity;bool armed;"
+		"fields": @( json.dumps(bytearray(";".join(topic_fields)+";", 'utf-8').decode('unicode_escape')) ),
+		"orb_ids": @( json.dumps([ all_topics.index(topic) for topic in topics]) ),
+		"main_orb_id": @( all_topics.index(name_snake_case) if name_snake_case in all_topics else -1 ),
+		"dependencies": @( json.dumps(list(set(dependencies))) ),
+		"name": "@( spec.full_name )"
+}

Tools/msg/templates/uorb/uORBTopics.cpp.em

@@ -8,7 +8,7 @@
 @#
 @# Context:
 @#  - msgs (List) list of all msg files
-@#  - multi_topics (List) list of all multi-topic names
+@#  - all_topics (List) list of all topic names (sorted)
 @###############################################
 /****************************************************************************
  *
@@ -50,9 +50,7 @@ msg_names = list(set([mn.replace(".msg", "") for mn in msgs])) # set() filters d
 msg_names.sort()
 msgs_count = len(msg_names)
 
-topic_names = list(set(topics)) # set() filters duplicates
-topic_names.sort()
-topics_count = len(topics)
+topics_count = len(all_topics)
 
 }@
 @[for msg_name in msg_names]@
@@ -60,8 +58,8 @@ topics_count = len(topics)
 @[end for]
 
 const constexpr struct orb_metadata *const uorb_topics_list[ORB_TOPICS_COUNT] = {
-@[for idx, topic_name in enumerate(topic_names, 1)]@
-	ORB_ID(@(topic_name))@[if idx != topic_names], @[end if]
+@[for idx, topic_name in enumerate(all_topics, 1)]@
+	ORB_ID(@(topic_name))@[if idx != all_topics], @[end if]
 @[end for]
 };
 

Tools/msg/templates/uorb/uORBTopics.hpp.em

@@ -7,7 +7,8 @@
 @# Start of Template
 @#
 @# Context:
-@#  - topics (List) list of all topic names
+@#  - msgs (List) list of all msg files
+@#  - all_topics (List) list of all topic names (sorted)
 @###############################################
 /****************************************************************************
  *
@@ -43,9 +44,7 @@
  ****************************************************************************/
 
 @{
-topics_count = len(topics)
-topic_names_all = list(set(topics)) # set() filters duplicates
-topic_names_all.sort()
+topics_count = len(all_topics)
 }@
 
 #pragma once
@@ -63,7 +62,7 @@ static constexpr size_t orb_topics_count() { return ORB_TOPICS_COUNT; }
 extern const struct orb_metadata *const *orb_get_topics() __EXPORT;
 
 enum class ORB_ID : orb_id_size_t {
-@[for idx, topic_name in enumerate(topic_names_all)]@
+@[for idx, topic_name in enumerate(all_topics)]@
 	@(topic_name) = @(idx),
 @[end for]
 	INVALID