User:Bugman/subsystems

Tracking down subsystems

Script

The following script is for finding all FlightGear dependencies:

Python script: Python script for finding all subsystems within the flightgear and simgear C++ code bases.

This script requires the grep Unix command, which can be installed on any OS. And it must be run with Python3.

#! /usr/bin/env python3

# Python module imports.
from argparse import ArgumentParser
import operator
from os import access, F_OK, sep
from re import search, split
from subprocess import PIPE, Popen
import sys


# Source code repository paths.
SIMGEAR_PATH = "/flightgear/src/flightgear-simgear"
FLIGHTGEAR_PATH = "/flightgear/src/flightgear-flightgear"

# Directories to exclude from the grep.
EXCLUDE_DIR = [
    ".git",
    "build*"
]


class FindSubsystems:
    """Class for finding all subsystems and subsystem groups."""

    def __init__(self):
        """Find all subsystems and subsystem groups."""

        # Command line options.
        self.parse_arguments()

        # SGSubsystem storage lists.
        self.subsystems = [[], [], [], []]
        self.groups = [[], [], [], []]

        # Grep exclude options.
        self.grep_exclude_dir = ""
        for name in EXCLUDE_DIR:
            self.grep_exclude_dir += "--exclude-dir \"%s\" " % name

        # The base objects.
        subsystem_base = Subsystem("SGSubsystem", xml=self.output_xml)
        group_base = Subsystem("SGSubsystemGroup", base_class=Subsystem("SGSubsystem"), xml=self.output_xml)

        # Add some problematic non-parsable classes.
        if self.category_subsystems:
            self.subsystems[1].append(Subsystem("FGAISim", base_class=Subsystem("FGInterface", base_class=Subsystem("SGSubsystem")), declaration_file="src/FDM/SP/AISim.hpp", xml=self.output_xml))

        # Find all SGSubsystem and SGSubsystemGroup derived classes.
        paths = [SIMGEAR_PATH, FLIGHTGEAR_PATH]
        for path in paths:
            if self.category_subsystems:
                self.find_primary(path=path, text="classes", primary=self.subsystems[0], base_name="SGSubsystem", base=subsystem_base, skip=["SGSubsystemGroup"])
            if self.category_groups:
                self.find_primary(path=path, text="groups", primary=self.groups[0], base_name="SGSubsystemGroup", base=group_base)

            if self.category_subsystems:
                self.find_secondary(path=path, text="classes", primary=self.subsystems[0], secondary=self.subsystems[1])
            if self.category_groups:
                self.find_secondary(path=path, text="groups", primary=self.groups[0], secondary=self.groups[1])

            if self.category_subsystems:
                self.find_tertiary(path=path, text="classes", secondary=self.subsystems[1], tertiary=self.subsystems[2])
            if self.category_groups:
                self.find_tertiary(path=path, text="groups", secondary=self.groups[1], tertiary=self.groups[2])

            if self.category_subsystems:
                self.find_quaternary(path=path, text="classes", tertiary=self.subsystems[2], quaternary=self.subsystems[3])
            if self.category_groups:
                self.find_quaternary(path=path, text="groups", tertiary=self.groups[2], quaternary=self.groups[3])

        # Find the subsystem and subsystem group implementation files.
        self.find_implementations()

        # Final summary.
        self.summarise()


    def count(self, storage_list):
        """Count the number of subsystems and subsystem groups.

        @param storage_list:    The data structure to count.
        @type storage_list:     list of Subsystem instances
        @return:                The number of subsystems and number of groups.
        @rtype:                 int, int
        """

        # Init.
        subsystems = 0
        groups = 0
        for element in storage_list:
            if element.is_group():
                groups += 1
            else:
                subsystems += 1

        # Return the counts.
        return subsystems, groups


    def find_implementations(self):
        """Find all implementation files for all subsystems and subsystem groups."""

        # Loop over all subsystems and groups.
        for subsystem in self.subsystems[0] + self.subsystems[1] + self.subsystems[2] + self.subsystems[3] + self.groups[0] + self.groups[1] + self.groups[2] + self.groups[3]:
            # The repository location.
            if subsystem.declaration_file[:7] == "simgear":
                path = SIMGEAR_PATH
            else:
                path = FLIGHTGEAR_PATH

            # The grep command for the ctor and dtor implementation.
            ctor = "\<%s\>::\<%s\>[ \(]" % (subsystem.name, subsystem.name)
            dtor = "\<%s\>::\~\<%s\>[ \(]" % (subsystem.name, subsystem.name)
            grep_ctor = 'grep -rI "%s\|%s"' % (ctor, dtor)

            # The grep command for any function implementation.
            grep_any = 'grep -rI %s "^[A-Za-z ]*\<%s\>::"' % (self.grep_exclude_dir, subsystem.name)

            # Search for matching file roots.
            if subsystem.declaration_file[-3:] == "hxx":
                # The probable implementation file name.
                file_name = subsystem.declaration_file[:-3] + "cxx"
                full_path = path + sep + file_name
                if access(full_path, F_OK):
                    # The Unix grep commands to run.
                    cmds = [
                        '%s %s' % (grep_ctor, full_path),
                        '%s %s | grep -v "return"' % (grep_any, full_path)
                    ]

                    # Search.
                    for cmd in cmds:
                        pipe = Popen(cmd, shell=True, stdout=PIPE)
                        lines = pipe.stdout.readlines()
                        if len(lines):
                            subsystem.implementation_file = file_name
                            break

            # Search everywhere.
            else:
                # The Unix grep commands to run.
                cmds = [
                    'cd %s; %s' % (path, grep_ctor),
                    'cd %s; %s | grep -v "return"' % (path, grep_any)
                ]

                # Search.
                for cmd in cmds:
                    pipe = Popen(cmd, shell=True, stdout=PIPE)

                    # Read all output.
                    files = []
                    for line in pipe.stdout.readlines():
                        # Convert the byte-array.
                        line = line.decode()

                        # Add the file if not already present.
                        file_name = line.split(":")[0]
                        if file_name not in files:
                            files.append(file_name)

                    # Bad grep.
                    if len(files) > 1:
                        sys.stderr.write("Warning: Excessive grep matching, too many implementation files found for:\n")
                        sys.stderr.write("    %s: %s\n" % (subsystem.name, files))

                    # Store the implementation file.
                    elif len(files):
                        subsystem.implementation_file = files[0]
                        break


    def find_primary(self, path=None, text=None, primary=None, base_name=None, base=None, skip=[]):
        """Find all primary subsystems and groups

        @keyword path:      The path to the repository to search through.
        @type path:         str
        @keyword text:      Text identifying subsystems vs. subsystem groups.
        @type text:         str
        @keyword primary:   The primary list of subsystems or groups.
        @type primary:      list of Subsystem instances
        @keyword base_name: The name of the base class.
        @type base_name:    str
        @keyword base:      The base class object.
        @type base:         Subsystem instance
        @keyword skip:      A list of class names to skip.
        @type skip:         list of str
        """

        # Printout.
        sys.stderr.write("Finding all primary %s in: %s\n" % (text, path))

        # Find all subsystems or groups.
        for file_name, class_name in self.grep(path=path, base_name=base_name):
            if class_name in skip:
                continue
            primary.append(Subsystem(class_name, base_class=base, declaration_file=file_name, xml=self.output_xml))

        # Sort the subsystems by name.
        primary.sort(key=operator.attrgetter('name'))


    def find_secondary(self, path=None, text=None, primary=None, secondary=None):
        """Find all secondary subsystems and groups

        @keyword path:      The path to the repository to search through.
        @type path:         str
        @keyword text:      Text identifying subsystems vs. subsystem groups.
        @type text:         str
        @keyword primary:   The primary list of subsystems or groups.
        @type primary:      list of Subsystem instances
        @keyword secondary: The secondary list of subsystems or groups.
        @type secondary:    list of Subsystem instances
        """

        # Printout.
        sys.stderr.write("Finding all secondary %s in: %s\n" % (text, path))

        # Loop over all primary subsystems.
        for subsystem in primary:
            for file_name, derived_class in self.grep(path=path, base_name=subsystem.name):
                secondary.append(Subsystem(derived_class, base_class=subsystem, declaration_file=file_name, xml=self.output_xml))

        # Sort the subsystems by name.
        secondary.sort(key=operator.attrgetter('name'))


    def find_tertiary(self, path=None, text=None, secondary=None, tertiary=None):
        """Find all tertiary subsystems and groups

        @keyword path:      The path to the repository to search through.
        @type path:         str
        @keyword text:      Text identifying subsystems vs. subsystem groups.
        @type text:         str
        @keyword secondary: The secondary list of subsystems or groups.
        @type secondary:    list of Subsystem instances
        @keyword tertiary:  The tertiary list of subsystems or groups.
        @type tertiary:     list of Subsystem instances
        """

        # Printout.
        sys.stderr.write("Finding all tertiary %s in: %s\n" % (text, path))

        # Loop over all secondary subsystems.
        for subsystem in secondary:
            for file_name, derived_class in self.grep(path=path, base_name=subsystem.name):
                tertiary.append(Subsystem(derived_class, base_class=subsystem, declaration_file=file_name, xml=self.output_xml))

        # Sort all subsystems by name.
        tertiary.sort(key=operator.attrgetter('name'))


    def find_quaternary(self, path=None, text=None, tertiary=None, quaternary=None):
        """Find all quaternary subsystems and groups

        @keyword path:          The path to the repository to search through.
        @type path:             str
        @keyword text:          Text identifying subsystems vs. subsystem groups.
        @type text:             str
        @keyword tertiary:      The tertiary list of subsystems or groups.
        @type tertiary:         list of Subsystem instances
        @keyword quaternary:    The quaternary list of subsystems or groups.
        @type quaternary:       list of Subsystem instances
        """

        # Printout.
        sys.stderr.write("Finding all quaternary %s in: %s\n" % (text, path))

        # Loop over all tertiary subsystems.
        for subsystem in tertiary:
            for file_name, derived_class in self.grep(path=path, base_name=subsystem.name):
                quaternary.append(Subsystem(derived_class, base_class=subsystem, declaration_file=file_name, xml=self.output_xml))

        # Sort all subsystems by name.
        quaternary.sort(key=operator.attrgetter('name'))


    def grep(self, path=None, base_name=None):
        """Generator method for finding all classes derived from the given base name and repository.

        @keyword path:      The path to the repository to search through.
        @type path:         str
        @keyword base_name: The name of the base class.
        @type base_name:    str
        @return:            The source file and the name of the derived class.
        @rtype:             str, str
        """

        # The Unix grep command to run.
        cmd = 'cd %s; grep -rI %s "public \<%s\>" | grep -v "%s::"' % (path, self.grep_exclude_dir, base_name, base_name)
        pipe = Popen(cmd, shell=True, stdout=PIPE)

        # Read all output.
        for line in pipe.stdout.readlines():
            # Convert the byte-array.
            line = line.decode()

            # Skip this script.
            if search("grep ", line):
                continue

            # Cannot handle this line!
            if not search("class ", line):
                sys.stderr.write("Skipping: %s\n" % repr(line[:-1]))
                continue

            # Split by single colons.
            elements = split("(?<!:):(?!:)", line)

            # The file and class name.
            file_name = elements[0]
            class_name = elements[1]
            class_name = class_name.replace("class", "")
            class_name = class_name.strip()

            # Generator method.
            yield file_name, class_name


    def parse_arguments(self):
        """Parse the command line arguments."""

        # The argument parser.
        parser = ArgumentParser()

        # The output arguments.
        group = parser.add_mutually_exclusive_group()
        group.add_argument("-t", "--text", default=False, action="store_true", help="Output in plain text format (the default).")
        group.add_argument("-x", "--xml", default=False, action="store_true", help="Output in XML format.")
        group.add_argument("-f", "--files", default=False, action="store_true", help="List all declaration and/or implementation files.")
        group.add_argument("-d", "--declaration-files", default=False, action="store_true", help="List the files where subsystems and subsystem groups are declared.")
        group.add_argument("-i", "--implementation-files", default=False, action="store_true", help="List the files where subsystems and subsystem groups are implemented.")

        # Category selection.
        group = parser.add_argument_group("category selections", "Choose between subsystems and subsystem groups.")
        group.add_argument("-n", "--no-groups", default=False, action="store_true", help="Skip subsystem groups.")
        group.add_argument("-g", "--groups", default=False, action="store_true", help="Only process subsystem groups.")

        # Parse the arguments.
        args = parser.parse_args()

        # The output arguments.
        self.output_xml = args.xml
        self.output_format = "text"
        if args.text:
            self.output_format = "text"
        elif args.xml:
            self.output_format = "xml"
        elif args.files:
            self.output_format = "files"
        elif args.declaration_files:
            self.output_format = "declaration files"
        elif args.implementation_files:
            self.output_format = "implementation files"

        # The category arguments.
        self.category_subsystems = True
        self.category_groups = True
        if args.groups:
            self.category_subsystems = False
        if args.no_groups:
            self.category_groups = False


    def summarise(self):
        """Print out a summary of all found subsystems and subsystem groups."""

        # Basic file listings.
        if self.output_format in ["files", "declaration files", "implementation files"]:
            # Concatenate the lists.
            subsystem_list = []
            if self.category_subsystems:
                subsystem_list += self.subsystems[0] + self.subsystems[1] + self.subsystems[2] + self.subsystems[3]
            if self.category_groups:
                subsystem_list += self.groups[0] + self.groups[1] + self.groups[2] + self.groups[3]

            # Loop over each subsystem, printing out the source files.
            for subsystem in subsystem_list:
                if self.output_format in ["files", "declaration files"]:
                    print(subsystem.declaration_file)
                if self.output_format in ["files", "implementation files"]:
                    if subsystem.implementation_file:
                        print(subsystem.implementation_file)

            # Skip the rest of the function.
            return

        # XML start.
        if self.output_xml:
            print("<?xml version=\"1.0\"?>")
            print("<subsystems>")

        # Subsystem and group printouts.
        labels = ["primary", "secondary", "tertiary", "quaternary"]
        labels2 = ["Primary", "Secondary", "Tertiary", "Quaternary"]
        classes = ["subsystems", "groups"]
        for i in range(len(self.subsystems)):
            for j in range(len(classes)):
                if classes[j] == "subsystems":
                    subsystem_list = self.subsystems[i]
                else:
                    subsystem_list = self.groups[i]

                # Nothing in the list.
                if not len(subsystem_list):
                    continue

                # Count all.
                counts = self.count(subsystem_list)

                # Start.
                if self.output_xml:
                    print("  <%s_%s count=\"%i\">" % (labels[i], classes[j], counts[j]))
                else:
                    print("\n%s %s (%i):" % (labels2[i], classes[j], counts[j]))

                # Subsystems.
                for subsystem in subsystem_list:
                    for line in repr(subsystem).split("\n"):
                        print("    %s" % (line))

                # End.
                if self.output_xml:
                    print("  </%s_%s>" % (labels[i], classes[j]))

        # Counts.
        subsystem_classes = len(self.subsystems[0] + self.subsystems[1] + self.subsystems[2] + self.subsystems[3])
        subsystem_groups = len(self.groups[0] + self.groups[1] + self.groups[2] + self.groups[3])
        subsystem_total = subsystem_classes + subsystem_groups

        # Separate simgear and flightgear subsystems.
        subsystem_classes_simgear = 0
        subsystem_classes_flightgear = 0
        subsystem_groups_simgear = 0
        subsystem_groups_flightgear = 0
        for subsystem in self.subsystems[0] + self.subsystems[1] + self.subsystems[2] + self.subsystems[3]:
            if subsystem.declaration_file[:7] == "simgear":
                subsystem_classes_simgear += 1
            else:
                subsystem_classes_flightgear += 1
        for group in self.groups[0] + self.groups[1] + self.groups[2] + self.groups[3]:
            if group.declaration_file[:7] == "simgear":
                subsystem_groups_simgear += 1
            else:
                subsystem_groups_flightgear += 1

        # Sums.
        simgear_total = subsystem_classes_simgear + subsystem_groups_simgear
        flightgear_total = subsystem_classes_flightgear + subsystem_groups_flightgear
        if self.output_xml:
            print("  <counts>")
            print("    <simgear>")
            if self.category_subsystems:
                print("      <subsystem_classes>%i</subsystem_classes>" % subsystem_classes_simgear)
            if self.category_groups:
                print("      <subsystem_groups>%i</subsystem_groups>" % subsystem_groups_simgear)
            if self.category_subsystems and self.category_groups:
                print("      <total>%i</total>" % simgear_total)
            print("    </simgear>")
            print("    <flightgear>")
            if self.category_subsystems:
                print("      <subsystem_classes>%i</subsystem_classes>" % subsystem_classes_flightgear)
            if self.category_groups:
                print("      <subsystem_groups>%i</subsystem_groups>" % subsystem_groups_flightgear)
            if self.category_subsystems and self.category_groups:
                print("      <total>%i</total>" % flightgear_total)
            print("    </flightgear>")
            print("    <combined>")
            if self.category_subsystems:
                print("      <subsystem_classes>%i</subsystem_classes>" % subsystem_classes)
            if self.category_groups:
                print("      <subsystem_groups>%i</subsystem_groups>" % subsystem_groups)
            if self.category_subsystems and self.category_groups:
                print("      <total>%i</total>" % subsystem_total)
            print("    </combined>")
            print("  </counts>")
        else:
            print("\nCounts: %i subsystem classes (%i flightgear, %i simgear)." % (subsystem_classes, subsystem_classes_flightgear, subsystem_classes_simgear))
            print("Counts: %i subsystem groups (%i flightgear, %i simgear)." % (subsystem_groups, subsystem_groups_flightgear, subsystem_groups_simgear))
            print("Counts: %i subsystem classes and groups (%i flightgear, %i simgear)." % (subsystem_total, flightgear_total, simgear_total))

        # XML end.
        if self.output_xml:
            print("</subsystems>")



class Subsystem:
    """Object for storing the information for a specific subsystem."""

    def __init__(self, name, base_class=None, declaration_file=None, implementation_file=None, xml=False):
        """Set up the object.

        @param name:                The name of the subsystem.
        @type name:                 str
        @keyword base_class:        The name of the base class.
        @type base_class:           str
        @keyword declaration_file:  The name of the file containing the subsystem declaration.
        @type declaration_file:     str
        @keyword implementation_file:  The name of the file containing the subsystem declaration.
        @type implementation_file:     str
        @keyword xml:               Produce a valid XML representation of the object.
        @type xml:                  bool
        """

        # Store the data.
        self.name = name
        self.base_class = base_class
        self.declaration_file = declaration_file
        self.implementation_file = implementation_file
        self.xml = xml


    def __repr__(self):
        """Overwrite the string representation of the object.

        @return:    The string representation.
        @rtype:     str
        """

        # The inheritance chain.
        inheritance = ""
        if self.base_class:
            inheritance += "%s" % self.base_class.name
            if self.base_class.base_class:
                inheritance += " : %s" % self.base_class.base_class.name
                if self.base_class.base_class.base_class:
                    inheritance += " : %s" % self.base_class.base_class.base_class.name
                    if self.base_class.base_class.base_class.base_class:
                        inheritance += " : %s" % self.base_class.base_class.base_class.base_class.name
                        if self.base_class.base_class.base_class.base_class.base_class:
                            inheritance += " : %s" % self.base_class.base_class.base_class.base_class.base_class.name

        # XML representation.
        if self.xml:
            return self.__repr_xml__(inheritance)

        # The subsystem name and inheritance chain.
        string = "<%s : %s" % (self.name, inheritance)

        # Add the declaration file name.
        string += " declared in \"%s\"" % self.declaration_file

        # Add the implementation file name.
        if self.implementation_file:
            string += ", implemented in \"%s\"" % self.implementation_file

        # Closure.
        string += ">"

        # Return the representation.
        return string


    def __repr_xml__(self, inheritance=""):
        """Create a XML representation of the object.

        @keyword inheritance:   The string representation of the inheritance chain.
        @type inheritance:      str
        @return:                The XML representation.
        @rtype:                 str
        """

        # Start.
        string = "<%s>\n" % self.name

        # The inheritance chain.
        string += "  <inheritance>%s</inheritance>\n" % inheritance

        # Add the declaration file name.
        string += "  <declaration>%s</declaration>\n" % self.declaration_file

        # Add the implementation file name.
        if self.implementation_file:
            string += "  <implementation>%s</implementation>\n" % self.implementation_file

        # End.
        string += "</%s>" % self.name

        # Return the string.
        return string


    def is_group(self):
        """Determine this is a subsystem or subsystem group.

        @return:    True if this is a subsystem group.
        @rtype:     bool
        """

        # Chase the base name as far as possible.
        if self.name == "SGSubsystemGroup":
            return True
        if self.base_class.name == "SGSubsystemGroup":
            return True
        if self.base_class.base_class:
            if self.base_class.base_class.name == "SGSubsystemGroup":
                return True
            if self.base_class.base_class.base_class:
                if self.base_class.base_class.base_class.name == "SGSubsystemGroup":
                    return True
                if self.base_class.base_class.base_class.base_class:
                    if self.base_class.base_class.base_class.base_class.name == "SGSubsystemGroup":
                        return True
                    if self.base_class.base_class.base_class.base_class.base_class:
                        if self.base_class.base_class.base_class.base_class.name.base_class.name == "SGSubsystemGroup":
                            return True

        # A normal subsystem.
        return False



# Instantiate the class if run as a script.
if __name__ == "__main__":
    FindSubsystems()

All subsystems

The result is:

Text output: A listing of all flightgear and simgear subsystems and subsystem groups.

Output from the Python script for finding all subsystems within the flightgear and simgear C++ code bases. The error output from the script was redirected and hence not shown below.

Primary subsystems (91):
    <ADF : SGSubsystem declared in "src/Instrumentation/adf.hxx", implemented in "src/Instrumentation/adf.cxx">
    <AirportDynamicsManager : SGSubsystem declared in "src/Airports/airportdynamicsmanager.hxx", implemented in "src/Airports/airportdynamicsmanager.cxx">
    <AirspeedIndicator : SGSubsystem declared in "src/Instrumentation/airspeed_indicator.hxx", implemented in "src/Instrumentation/airspeed_indicator.cxx">
    <Altimeter : SGSubsystem declared in "src/Instrumentation/altimeter.hxx", implemented in "src/Instrumentation/altimeter.cxx">
    <AreaSampler : SGSubsystem declared in "src/Environment/terrainsampler.cxx", implemented in "src/Environment/terrainsampler.cxx">
    <AttitudeIndicator : SGSubsystem declared in "src/Instrumentation/attitude_indicator.hxx", implemented in "src/Instrumentation/attitude_indicator.cxx">
    <Clock : SGSubsystem declared in "src/Instrumentation/clock.hxx", implemented in "src/Instrumentation/clock.cxx">
    <CommRadio : SGSubsystem declared in "src/Instrumentation/commradio.hxx">
    <Component : SGSubsystem declared in "src/Autopilot/component.hxx", implemented in "src/Autopilot/component.cxx">
    <DCLGPS : SGSubsystem declared in "src/Instrumentation/dclgps.hxx", implemented in "src/Instrumentation/dclgps.cxx">
    <DME : SGSubsystem declared in "src/Instrumentation/dme.hxx", implemented in "src/Instrumentation/dme.cxx">
    <Ephemeris : SGSubsystem declared in "src/Environment/ephemeris.hxx", implemented in "src/Environment/ephemeris.cxx">
    <FDMShell : SGSubsystem declared in "src/FDM/fdm_shell.hxx", implemented in "src/FDM/fdm_shell.cxx">
    <FGAIManager : SGSubsystem declared in "src/AIModel/AIManager.hxx", implemented in "src/AIModel/AIManager.cxx">
    <FGATCManager : SGSubsystem declared in "src/ATC/atc_mgr.hxx", implemented in "src/ATC/atc_mgr.cxx">
    <FGAircraftModel : SGSubsystem declared in "src/Model/acmodel.hxx", implemented in "src/Model/acmodel.cxx">
    <FGCom : SGSubsystem declared in "src/Network/fgcom.hxx", implemented in "src/Network/fgcom.cxx">
    <FGControls : SGSubsystem declared in "src/Aircraft/controls.hxx", implemented in "src/Aircraft/controls.cxx">
    <FGDNSClient : SGSubsystem declared in "src/Network/DNSClient.hxx", implemented in "src/Network/DNSClient.cxx">
    <FGElectricalSystem : SGSubsystem declared in "src/Systems/electrical.hxx", implemented in "src/Systems/electrical.cxx">
    <FGEventInput : SGSubsystem declared in "src/Input/FGEventInput.hxx", implemented in "src/Input/FGEventInput.cxx">
    <FGFlightHistory : SGSubsystem declared in "src/Aircraft/FlightHistory.hxx", implemented in "src/Aircraft/FlightHistory.cxx">
    <FGHTTPClient : SGSubsystem declared in "src/Network/HTTPClient.hxx", implemented in "src/Network/HTTPClient.cxx">
    <FGHttpd : SGSubsystem declared in "src/Network/http/httpd.hxx">
    <FGIO : SGSubsystem declared in "src/Main/fg_io.hxx", implemented in "src/Main/fg_io.cxx">
    <FGInterface : SGSubsystem declared in "src/FDM/flight.hxx", implemented in "src/FDM/flight.cxx">
    <FGJoystickInput : SGSubsystem declared in "src/Input/FGJoystickInput.hxx", implemented in "src/Input/FGJoystickInput.cxx">
    <FGKR_87 : SGSubsystem declared in "src/Instrumentation/kr_87.hxx", implemented in "src/Instrumentation/kr_87.cxx">
    <FGKeyboardInput : SGSubsystem declared in "src/Input/FGKeyboardInput.hxx", implemented in "src/Input/FGKeyboardInput.cxx">
    <FGLight : SGSubsystem declared in "src/Time/light.hxx", implemented in "src/Time/light.cxx">
    <FGLogger : SGSubsystem declared in "src/Main/logger.hxx", implemented in "src/Main/logger.cxx">
    <FGMagVarManager : SGSubsystem declared in "src/Environment/magvarmanager.hxx", implemented in "src/Environment/magvarmanager.cxx">
    <FGMarkerBeacon : SGSubsystem declared in "src/Instrumentation/marker_beacon.hxx", implemented in "src/Instrumentation/marker_beacon.cxx">
    <FGModelMgr : SGSubsystem declared in "src/Model/modelmgr.hxx", implemented in "src/Model/modelmgr.cxx">
    <FGMouseInput : SGSubsystem declared in "src/Input/FGMouseInput.hxx", implemented in "src/Input/FGMouseInput.cxx">
    <FGMultiplayMgr : SGSubsystem declared in "src/MultiPlayer/multiplaymgr.hxx", implemented in "src/MultiPlayer/multiplaymgr.cxx">
    <FGNasalSys : SGSubsystem declared in "src/Scripting/NasalSys.hxx", implemented in "src/Scripting/NasalSys.cxx">
    <FGNavRadio : SGSubsystem declared in "src/Instrumentation/navradio.hxx", implemented in "src/Instrumentation/navradio.cxx">
    <FGPanel : SGSubsystem declared in "utils/fgpanel/FGPanel.hxx", implemented in "utils/fgpanel/FGPanel.cxx">
    <FGPanelProtocol : SGSubsystem declared in "utils/fgpanel/FGPanelProtocol.hxx", implemented in "utils/fgpanel/FGPanelProtocol.cxx">
    <FGPrecipitationMgr : SGSubsystem declared in "src/Environment/precipitation_mgr.hxx", implemented in "src/Environment/precipitation_mgr.cxx">
    <FGProperties : SGSubsystem declared in "src/Main/fg_props.hxx", implemented in "src/Main/fg_props.cxx">
    <FGReplay : SGSubsystem declared in "src/Aircraft/replay.hxx", implemented in "src/Aircraft/replay.cxx">
    <FGRidgeLift : SGSubsystem declared in "src/Environment/ridge_lift.hxx", implemented in "src/Environment/ridge_lift.cxx">
    <FGRouteMgr : SGSubsystem declared in "src/Autopilot/route_mgr.hxx", implemented in "src/Autopilot/route_mgr.cxx">
    <FGScenery : SGSubsystem declared in "src/Scenery/scenery.hxx", implemented in "src/Scenery/scenery.cxx">
    <FGSoundManager : SGSubsystem declared in "src/Sound/soundmanager.hxx", implemented in "src/Sound/soundmanager.cxx">
    <FGSubmodelMgr : SGSubsystem declared in "src/AIModel/submodel.hxx", implemented in "src/AIModel/submodel.cxx">
    <FGSubsystemExample : SGSubsystem declared in "docs-mini/README.introduction", implemented in "docs-mini/README.introduction">
    <FGTrafficManager : SGSubsystem declared in "src/Traffic/TrafficMgr.hxx", implemented in "src/Traffic/TrafficMgr.cxx">
    <FGViewMgr : SGSubsystem declared in "src/Viewer/viewmgr.hxx", implemented in "src/Viewer/viewmgr.cxx">
    <FGVoiceMgr : SGSubsystem declared in "src/Sound/voice.hxx", implemented in "src/Sound/voice.cxx">
    <GPS : SGSubsystem declared in "src/Instrumentation/gps.hxx", implemented in "src/Instrumentation/gps.cxx">
    <GSDI : SGSubsystem declared in "src/Instrumentation/gsdi.hxx", implemented in "src/Instrumentation/gsdi.cxx">
    <GUIMgr : SGSubsystem declared in "src/Canvas/gui_mgr.hxx", implemented in "src/Canvas/gui_mgr.cxx">
    <GroundRadar : SGSubsystem declared in "src/Cockpit/groundradar.hxx", implemented in "src/Cockpit/groundradar.cxx">
    <HUD : SGSubsystem declared in "src/Instrumentation/HUD/HUD.hxx", implemented in "src/Instrumentation/HUD/HUD.cxx">
    <HeadingIndicator : SGSubsystem declared in "src/Instrumentation/heading_indicator.hxx", implemented in "src/Instrumentation/heading_indicator.cxx">
    <HeadingIndicatorDG : SGSubsystem declared in "src/Instrumentation/heading_indicator_dg.hxx", implemented in "src/Instrumentation/heading_indicator_dg.cxx">
    <HeadingIndicatorFG : SGSubsystem declared in "src/Instrumentation/heading_indicator_fg.hxx", implemented in "src/Instrumentation/heading_indicator_fg.cxx">
    <InstVerticalSpeedIndicator : SGSubsystem declared in "src/Instrumentation/inst_vertical_speed_indicator.hxx", implemented in "src/Instrumentation/inst_vertical_speed_indicator.cxx">
    <LayerInterpolateController : SGSubsystem declared in "src/Environment/environment_ctrl.hxx">
    <MK_VIII : SGSubsystem declared in "src/Instrumentation/mk_viii.hxx", implemented in "src/Instrumentation/mk_viii.cxx">
    <MagCompass : SGSubsystem declared in "src/Instrumentation/mag_compass.hxx", implemented in "src/Instrumentation/mag_compass.cxx">
    <MasterReferenceGyro : SGSubsystem declared in "src/Instrumentation/mrg.hxx", implemented in "src/Instrumentation/mrg.cxx">
    <NavDisplay : SGSubsystem declared in "src/Cockpit/NavDisplay.hxx", implemented in "src/Cockpit/NavDisplay.cxx">
    <NavRadio : SGSubsystem declared in "src/Instrumentation/newnavradio.hxx">
    <NewGUI : SGSubsystem declared in "src/GUI/new_gui.hxx", implemented in "src/GUI/new_gui.cxx">
    <PerformanceDB : SGSubsystem declared in "src/AIModel/performancedb.hxx", implemented in "src/AIModel/performancedb.cxx">
    <PitotSystem : SGSubsystem declared in "src/Systems/pitot.hxx", implemented in "src/Systems/pitot.cxx">
    <PropertyBasedMgr : SGSubsystem declared in "simgear/props/PropertyBasedMgr.hxx", implemented in "simgear/props/PropertyBasedMgr.cxx">
    <PropertyInterpolationMgr : SGSubsystem declared in "simgear/props/PropertyInterpolationMgr.hxx", implemented in "simgear/props/PropertyInterpolationMgr.cxx">
    <RadarAltimeter : SGSubsystem declared in "src/Instrumentation/rad_alt.hxx", implemented in "src/Instrumentation/rad_alt.cxx">
    <RealWxController : SGSubsystem declared in "src/Environment/realwx_ctrl.hxx", implemented in "src/Environment/realwx_ctrl.cxx">
    <SGEventMgr : SGSubsystem declared in "simgear/structure/event_mgr.hxx", implemented in "simgear/structure/event_mgr.cxx">
    <SGInterpolator : SGSubsystem declared in "simgear/misc/interpolator.hxx", implemented in "simgear/misc/interpolator.cxx">
    <SGPerformanceMonitor : SGSubsystem declared in "simgear/structure/SGPerfMon.hxx", implemented in "simgear/structure/SGPerfMon.cxx">
    <SGSoundMgr : SGSubsystem declared in "simgear/sound/soundmgr.hxx">
    <SGSubsystemMgr : SGSubsystem declared in "simgear/structure/subsystem_mgr.hxx", implemented in "simgear/structure/subsystem_mgr.cxx">
    <SGTerraSync : SGSubsystem declared in "simgear/scene/tsync/terrasync.hxx", implemented in "simgear/scene/tsync/terrasync.cxx">
    <SlipSkidBall : SGSubsystem declared in "src/Instrumentation/slip_skid_ball.hxx", implemented in "src/Instrumentation/slip_skid_ball.cxx">
    <StaticSystem : SGSubsystem declared in "src/Systems/static.hxx", implemented in "src/Systems/static.cxx">
    <TACAN : SGSubsystem declared in "src/Instrumentation/tacan.hxx", implemented in "src/Instrumentation/tacan.cxx">
    <TCAS : SGSubsystem declared in "src/Instrumentation/tcas.hxx", implemented in "src/Instrumentation/tcas.cxx">
    <TimeManager : SGSubsystem declared in "src/Time/TimeManager.hxx", implemented in "src/Time/TimeManager.cxx">
    <Transponder : SGSubsystem declared in "src/Instrumentation/transponder.hxx", implemented in "src/Instrumentation/transponder.cxx">
    <TurnIndicator : SGSubsystem declared in "src/Instrumentation/turn_indicator.hxx", implemented in "src/Instrumentation/turn_indicator.cxx">
    <VacuumSystem : SGSubsystem declared in "src/Systems/vacuum.hxx", implemented in "src/Systems/vacuum.cxx">
    <VerticalSpeedIndicator : SGSubsystem declared in "src/Instrumentation/vertical_speed_indicator.hxx", implemented in "src/Instrumentation/vertical_speed_indicator.cxx">
    <View : SGSubsystem declared in "src/Viewer/view.hxx", implemented in "src/Viewer/view.cxx">
    <wxRadarBg : SGSubsystem declared in "src/Cockpit/wxradar.hxx", implemented in "src/Cockpit/wxradar.cxx">

Primary groups (8):
    <Autopilot : SGSubsystemGroup : SGSubsystem declared in "src/Autopilot/autopilot.hxx", implemented in "src/Autopilot/autopilot.cxx">
    <CockpitDisplayManager : SGSubsystemGroup : SGSubsystem declared in "src/Cockpit/cockpitDisplayManager.hxx", implemented in "src/Cockpit/cockpitDisplayManager.cxx">
    <FGEnvironmentMgr : SGSubsystemGroup : SGSubsystem declared in "src/Environment/environment_mgr.hxx", implemented in "src/Environment/environment_mgr.cxx">
    <FGInput : SGSubsystemGroup : SGSubsystem declared in "src/Input/input.hxx", implemented in "src/Input/input.cxx">
    <FGInstrumentMgr : SGSubsystemGroup : SGSubsystem declared in "src/Instrumentation/instrument_mgr.hxx", implemented in "src/Instrumentation/instrument_mgr.cxx">
    <FGSystemMgr : SGSubsystemGroup : SGSubsystem declared in "src/Systems/system_mgr.hxx", implemented in "src/Systems/system_mgr.cxx">
    <FGXMLAutopilotGroup : SGSubsystemGroup : SGSubsystem declared in "src/Autopilot/autopilotgroup.hxx", implemented in "src/Autopilot/autopilotgroup.cxx">
    <TerrainSampler : SGSubsystemGroup : SGSubsystem declared in "src/Environment/terrainsampler.hxx">

Secondary subsystems (28):
    <AnalogComponent : Component : SGSubsystem declared in "src/Autopilot/analogcomponent.hxx", implemented in "src/Autopilot/analogcomponent.cxx">
    <BasicRealWxController : RealWxController : SGSubsystem declared in "src/Environment/realwx_ctrl.cxx", implemented in "src/Environment/realwx_ctrl.cxx">
    <CanvasMgr : PropertyBasedMgr : SGSubsystem declared in "simgear/canvas/CanvasMgr.hxx", implemented in "simgear/canvas/CanvasMgr.cxx">
    <CommRadioImpl : CommRadio : SGSubsystem declared in "src/Instrumentation/commradio.cxx", implemented in "src/Instrumentation/commradio.cxx">
    <DigitalComponent : Component : SGSubsystem declared in "src/Autopilot/digitalcomponent.hxx", implemented in "src/Autopilot/digitalcomponent.cxx">
    <FGACMS : FGInterface : SGSubsystem declared in "src/FDM/SP/ACMS.hxx", implemented in "src/FDM/SP/ACMS.cxx">
    <FGADA : FGInterface : SGSubsystem declared in "src/FDM/SP/ADA.hxx", implemented in "src/FDM/SP/ADA.cxx">
    <FGAISim : FGInterface : SGSubsystem declared in "src/FDM/SP/AISim.hpp", implemented in "src/FDM/SP/AISim.cpp">
    <FGBalloonSim : FGInterface : SGSubsystem declared in "src/FDM/SP/Balloon.h", implemented in "src/FDM/SP/Balloon.cxx">
    <FGExternalNet : FGInterface : SGSubsystem declared in "src/FDM/ExternalNet/ExternalNet.hxx", implemented in "src/FDM/ExternalNet/ExternalNet.cxx">
    <FGExternalPipe : FGInterface : SGSubsystem declared in "src/FDM/ExternalPipe/ExternalPipe.hxx", implemented in "src/FDM/ExternalPipe/ExternalPipe.cxx">
    <FGHIDEventInput : FGEventInput : SGSubsystem declared in "src/Input/FGHIDEventInput.hxx", implemented in "src/Input/FGHIDEventInput.cxx">
    <FGJSBsim : FGInterface : SGSubsystem declared in "src/FDM/JSBSim/JSBSim.hxx", implemented in "src/FDM/JSBSim/JSBSim.cxx">
    <FGLaRCsim : FGInterface : SGSubsystem declared in "src/FDM/LaRCsim/LaRCsim.hxx", implemented in "src/FDM/LaRCsim/LaRCsim.cxx">
    <FGLinuxEventInput : FGEventInput : SGSubsystem declared in "src/Input/FGLinuxEventInput.hxx", implemented in "src/Input/FGLinuxEventInput.cxx">
    <FGMacOSXEventInput : FGEventInput : SGSubsystem declared in "src/Input/FGMacOSXEventInput.hxx", implemented in "src/Input/FGMacOSXEventInput.cxx">
    <FGMagicCarpet : FGInterface : SGSubsystem declared in "src/FDM/SP/MagicCarpet.hxx", implemented in "src/FDM/SP/MagicCarpet.cxx">
    <FGNullFDM : FGInterface : SGSubsystem declared in "src/FDM/NullFDM.hxx", implemented in "src/FDM/NullFDM.cxx">
    <FGReadablePanel : FGPanel : SGSubsystem declared in "utils/fgpanel/panel_io.hxx", implemented in "utils/fgpanel/panel_io.cxx">
    <FGSoundManager : SGSoundMgr : SGSubsystem declared in "src/Sound/soundmanager.hxx", implemented in "src/Sound/soundmanager.cxx">
    <FGUFO : FGInterface : SGSubsystem declared in "src/FDM/UFO.hxx", implemented in "src/FDM/UFO.cxx">
    <KLN89 : DCLGPS : SGSubsystem declared in "src/Instrumentation/KLN89/kln89.hxx", implemented in "src/Instrumentation/KLN89/kln89.cxx">
    <LayerInterpolateControllerImplementation : LayerInterpolateController : SGSubsystem declared in "src/Environment/environment_ctrl.cxx", implemented in "src/Environment/environment_ctrl.cxx">
    <MongooseHttpd : FGHttpd : SGSubsystem declared in "src/Network/http/httpd.cxx", implemented in "src/Network/http/httpd.cxx">
    <NavRadioImpl : NavRadio : SGSubsystem declared in "src/Instrumentation/newnavradio.cxx", implemented in "src/Instrumentation/newnavradio.cxx">
    <StateMachineComponent : Component : SGSubsystem declared in "src/Autopilot/autopilot.cxx", implemented in "src/Autopilot/autopilot.cxx">
    <YASim : FGInterface : SGSubsystem declared in "src/FDM/YASim/YASim.hxx", implemented in "src/FDM/YASim/YASim.cxx">
    <agRadar : wxRadarBg : SGSubsystem declared in "src/Cockpit/agradar.hxx", implemented in "src/Cockpit/agradar.cxx">

Secondary groups (2):
    <FGXMLAutopilotGroupImplementation : FGXMLAutopilotGroup : SGSubsystemGroup : SGSubsystem declared in "src/Autopilot/autopilotgroup.cxx", implemented in "src/Autopilot/autopilotgroup.cxx">
    <TerrainSamplerImplementation : TerrainSampler : SGSubsystemGroup : SGSubsystem declared in "src/Environment/terrainsampler.cxx", implemented in "src/Environment/terrainsampler.cxx">

Tertiary subsystems (6):
    <DigitalFilter : AnalogComponent : Component : SGSubsystem declared in "src/Autopilot/digitalfilter.hxx", implemented in "src/Autopilot/digitalfilter.cxx">
    <Logic : DigitalComponent : Component : SGSubsystem declared in "src/Autopilot/logic.hxx", implemented in "src/Autopilot/logic.cxx">
    <NoaaMetarRealWxController : BasicRealWxController : RealWxController : SGSubsystem declared in "src/Environment/realwx_ctrl.cxx", implemented in "src/Environment/realwx_ctrl.cxx">
    <PIDController : AnalogComponent : Component : SGSubsystem declared in "src/Autopilot/pidcontroller.hxx", implemented in "src/Autopilot/pidcontroller.cxx">
    <PISimpleController : AnalogComponent : Component : SGSubsystem declared in "src/Autopilot/pisimplecontroller.hxx", implemented in "src/Autopilot/pisimplecontroller.cxx">
    <Predictor : AnalogComponent : Component : SGSubsystem declared in "src/Autopilot/predictor.hxx", implemented in "src/Autopilot/predictor.cxx">

Quaternary subsystems (1):
    <FlipFlop : Logic : DigitalComponent : Component : SGSubsystem declared in "src/Autopilot/flipflop.hxx", implemented in "src/Autopilot/flipflop.cxx">

Counts: 126 subsystem classes (117 flightgear, 9 simgear).
Counts: 10 subsystem groups (10 flightgear, 0 simgear).
Counts: 136 subsystem classes and groups (127 flightgear, 9 simgear).

XML output: A listing of all flightgear and simgear subsystems and subsystem groups.

XML output from the Python script for finding all subsystems within the flightgear and simgear C++ code bases. The error output from the script was redirected and hence not shown below.

<?xml version="1.0"?>
<subsystems>
  <primary_subsystems count="91">
    <ADF>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/adf.hxx</declaration>
      <implementation>src/Instrumentation/adf.cxx</implementation>
    </ADF>
    <AirportDynamicsManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Airports/airportdynamicsmanager.hxx</declaration>
      <implementation>src/Airports/airportdynamicsmanager.cxx</implementation>
    </AirportDynamicsManager>
    <AirspeedIndicator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/airspeed_indicator.hxx</declaration>
      <implementation>src/Instrumentation/airspeed_indicator.cxx</implementation>
    </AirspeedIndicator>
    <Altimeter>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/altimeter.hxx</declaration>
      <implementation>src/Instrumentation/altimeter.cxx</implementation>
    </Altimeter>
    <AreaSampler>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/terrainsampler.cxx</declaration>
      <implementation>src/Environment/terrainsampler.cxx</implementation>
    </AreaSampler>
    <AttitudeIndicator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/attitude_indicator.hxx</declaration>
      <implementation>src/Instrumentation/attitude_indicator.cxx</implementation>
    </AttitudeIndicator>
    <Clock>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/clock.hxx</declaration>
      <implementation>src/Instrumentation/clock.cxx</implementation>
    </Clock>
    <CommRadio>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/commradio.hxx</declaration>
    </CommRadio>
    <Component>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Autopilot/component.hxx</declaration>
      <implementation>src/Autopilot/component.cxx</implementation>
    </Component>
    <DCLGPS>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/dclgps.hxx</declaration>
      <implementation>src/Instrumentation/dclgps.cxx</implementation>
    </DCLGPS>
    <DME>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/dme.hxx</declaration>
      <implementation>src/Instrumentation/dme.cxx</implementation>
    </DME>
    <Ephemeris>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/ephemeris.hxx</declaration>
      <implementation>src/Environment/ephemeris.cxx</implementation>
    </Ephemeris>
    <FDMShell>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/FDM/fdm_shell.hxx</declaration>
      <implementation>src/FDM/fdm_shell.cxx</implementation>
    </FDMShell>
    <FGAIManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/AIModel/AIManager.hxx</declaration>
      <implementation>src/AIModel/AIManager.cxx</implementation>
    </FGAIManager>
    <FGATCManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/ATC/atc_mgr.hxx</declaration>
      <implementation>src/ATC/atc_mgr.cxx</implementation>
    </FGATCManager>
    <FGAircraftModel>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Model/acmodel.hxx</declaration>
      <implementation>src/Model/acmodel.cxx</implementation>
    </FGAircraftModel>
    <FGCom>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Network/fgcom.hxx</declaration>
      <implementation>src/Network/fgcom.cxx</implementation>
    </FGCom>
    <FGControls>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Aircraft/controls.hxx</declaration>
      <implementation>src/Aircraft/controls.cxx</implementation>
    </FGControls>
    <FGDNSClient>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Network/DNSClient.hxx</declaration>
      <implementation>src/Network/DNSClient.cxx</implementation>
    </FGDNSClient>
    <FGElectricalSystem>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Systems/electrical.hxx</declaration>
      <implementation>src/Systems/electrical.cxx</implementation>
    </FGElectricalSystem>
    <FGEventInput>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Input/FGEventInput.hxx</declaration>
      <implementation>src/Input/FGEventInput.cxx</implementation>
    </FGEventInput>
    <FGFlightHistory>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Aircraft/FlightHistory.hxx</declaration>
      <implementation>src/Aircraft/FlightHistory.cxx</implementation>
    </FGFlightHistory>
    <FGHTTPClient>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Network/HTTPClient.hxx</declaration>
      <implementation>src/Network/HTTPClient.cxx</implementation>
    </FGHTTPClient>
    <FGHttpd>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Network/http/httpd.hxx</declaration>
    </FGHttpd>
    <FGIO>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Main/fg_io.hxx</declaration>
      <implementation>src/Main/fg_io.cxx</implementation>
    </FGIO>
    <FGInterface>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/FDM/flight.hxx</declaration>
      <implementation>src/FDM/flight.cxx</implementation>
    </FGInterface>
    <FGJoystickInput>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Input/FGJoystickInput.hxx</declaration>
      <implementation>src/Input/FGJoystickInput.cxx</implementation>
    </FGJoystickInput>
    <FGKR_87>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/kr_87.hxx</declaration>
      <implementation>src/Instrumentation/kr_87.cxx</implementation>
    </FGKR_87>
    <FGKeyboardInput>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Input/FGKeyboardInput.hxx</declaration>
      <implementation>src/Input/FGKeyboardInput.cxx</implementation>
    </FGKeyboardInput>
    <FGLight>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Time/light.hxx</declaration>
      <implementation>src/Time/light.cxx</implementation>
    </FGLight>
    <FGLogger>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Main/logger.hxx</declaration>
      <implementation>src/Main/logger.cxx</implementation>
    </FGLogger>
    <FGMagVarManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/magvarmanager.hxx</declaration>
      <implementation>src/Environment/magvarmanager.cxx</implementation>
    </FGMagVarManager>
    <FGMarkerBeacon>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/marker_beacon.hxx</declaration>
      <implementation>src/Instrumentation/marker_beacon.cxx</implementation>
    </FGMarkerBeacon>
    <FGModelMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Model/modelmgr.hxx</declaration>
      <implementation>src/Model/modelmgr.cxx</implementation>
    </FGModelMgr>
    <FGMouseInput>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Input/FGMouseInput.hxx</declaration>
      <implementation>src/Input/FGMouseInput.cxx</implementation>
    </FGMouseInput>
    <FGMultiplayMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/MultiPlayer/multiplaymgr.hxx</declaration>
      <implementation>src/MultiPlayer/multiplaymgr.cxx</implementation>
    </FGMultiplayMgr>
    <FGNasalSys>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Scripting/NasalSys.hxx</declaration>
      <implementation>src/Scripting/NasalSys.cxx</implementation>
    </FGNasalSys>
    <FGNavRadio>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/navradio.hxx</declaration>
      <implementation>src/Instrumentation/navradio.cxx</implementation>
    </FGNavRadio>
    <FGPanel>
      <inheritance>SGSubsystem</inheritance>
      <declaration>utils/fgpanel/FGPanel.hxx</declaration>
      <implementation>utils/fgpanel/FGPanel.cxx</implementation>
    </FGPanel>
    <FGPanelProtocol>
      <inheritance>SGSubsystem</inheritance>
      <declaration>utils/fgpanel/FGPanelProtocol.hxx</declaration>
      <implementation>utils/fgpanel/FGPanelProtocol.cxx</implementation>
    </FGPanelProtocol>
    <FGPrecipitationMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/precipitation_mgr.hxx</declaration>
      <implementation>src/Environment/precipitation_mgr.cxx</implementation>
    </FGPrecipitationMgr>
    <FGProperties>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Main/fg_props.hxx</declaration>
      <implementation>src/Main/fg_props.cxx</implementation>
    </FGProperties>
    <FGReplay>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Aircraft/replay.hxx</declaration>
      <implementation>src/Aircraft/replay.cxx</implementation>
    </FGReplay>
    <FGRidgeLift>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/ridge_lift.hxx</declaration>
      <implementation>src/Environment/ridge_lift.cxx</implementation>
    </FGRidgeLift>
    <FGRouteMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Autopilot/route_mgr.hxx</declaration>
      <implementation>src/Autopilot/route_mgr.cxx</implementation>
    </FGRouteMgr>
    <FGScenery>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Scenery/scenery.hxx</declaration>
      <implementation>src/Scenery/scenery.cxx</implementation>
    </FGScenery>
    <FGSoundManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Sound/soundmanager.hxx</declaration>
      <implementation>src/Sound/soundmanager.cxx</implementation>
    </FGSoundManager>
    <FGSubmodelMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/AIModel/submodel.hxx</declaration>
      <implementation>src/AIModel/submodel.cxx</implementation>
    </FGSubmodelMgr>
    <FGSubsystemExample>
      <inheritance>SGSubsystem</inheritance>
      <declaration>docs-mini/README.introduction</declaration>
      <implementation>docs-mini/README.introduction</implementation>
    </FGSubsystemExample>
    <FGTrafficManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Traffic/TrafficMgr.hxx</declaration>
      <implementation>src/Traffic/TrafficMgr.cxx</implementation>
    </FGTrafficManager>
    <FGViewMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Viewer/viewmgr.hxx</declaration>
      <implementation>src/Viewer/viewmgr.cxx</implementation>
    </FGViewMgr>
    <FGVoiceMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Sound/voice.hxx</declaration>
      <implementation>src/Sound/voice.cxx</implementation>
    </FGVoiceMgr>
    <GPS>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/gps.hxx</declaration>
      <implementation>src/Instrumentation/gps.cxx</implementation>
    </GPS>
    <GSDI>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/gsdi.hxx</declaration>
      <implementation>src/Instrumentation/gsdi.cxx</implementation>
    </GSDI>
    <GUIMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Canvas/gui_mgr.hxx</declaration>
      <implementation>src/Canvas/gui_mgr.cxx</implementation>
    </GUIMgr>
    <GroundRadar>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Cockpit/groundradar.hxx</declaration>
      <implementation>src/Cockpit/groundradar.cxx</implementation>
    </GroundRadar>
    <HUD>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/HUD/HUD.hxx</declaration>
      <implementation>src/Instrumentation/HUD/HUD.cxx</implementation>
    </HUD>
    <HeadingIndicator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/heading_indicator.hxx</declaration>
      <implementation>src/Instrumentation/heading_indicator.cxx</implementation>
    </HeadingIndicator>
    <HeadingIndicatorDG>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/heading_indicator_dg.hxx</declaration>
      <implementation>src/Instrumentation/heading_indicator_dg.cxx</implementation>
    </HeadingIndicatorDG>
    <HeadingIndicatorFG>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/heading_indicator_fg.hxx</declaration>
      <implementation>src/Instrumentation/heading_indicator_fg.cxx</implementation>
    </HeadingIndicatorFG>
    <InstVerticalSpeedIndicator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/inst_vertical_speed_indicator.hxx</declaration>
      <implementation>src/Instrumentation/inst_vertical_speed_indicator.cxx</implementation>
    </InstVerticalSpeedIndicator>
    <LayerInterpolateController>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/environment_ctrl.hxx</declaration>
    </LayerInterpolateController>
    <MK_VIII>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/mk_viii.hxx</declaration>
      <implementation>src/Instrumentation/mk_viii.cxx</implementation>
    </MK_VIII>
    <MagCompass>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/mag_compass.hxx</declaration>
      <implementation>src/Instrumentation/mag_compass.cxx</implementation>
    </MagCompass>
    <MasterReferenceGyro>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/mrg.hxx</declaration>
      <implementation>src/Instrumentation/mrg.cxx</implementation>
    </MasterReferenceGyro>
    <NavDisplay>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Cockpit/NavDisplay.hxx</declaration>
      <implementation>src/Cockpit/NavDisplay.cxx</implementation>
    </NavDisplay>
    <NavRadio>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/newnavradio.hxx</declaration>
    </NavRadio>
    <NewGUI>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/GUI/new_gui.hxx</declaration>
      <implementation>src/GUI/new_gui.cxx</implementation>
    </NewGUI>
    <PerformanceDB>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/AIModel/performancedb.hxx</declaration>
      <implementation>src/AIModel/performancedb.cxx</implementation>
    </PerformanceDB>
    <PitotSystem>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Systems/pitot.hxx</declaration>
      <implementation>src/Systems/pitot.cxx</implementation>
    </PitotSystem>
    <PropertyBasedMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/props/PropertyBasedMgr.hxx</declaration>
      <implementation>simgear/props/PropertyBasedMgr.cxx</implementation>
    </PropertyBasedMgr>
    <PropertyInterpolationMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/props/PropertyInterpolationMgr.hxx</declaration>
      <implementation>simgear/props/PropertyInterpolationMgr.cxx</implementation>
    </PropertyInterpolationMgr>
    <RadarAltimeter>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/rad_alt.hxx</declaration>
      <implementation>src/Instrumentation/rad_alt.cxx</implementation>
    </RadarAltimeter>
    <RealWxController>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Environment/realwx_ctrl.hxx</declaration>
      <implementation>src/Environment/realwx_ctrl.cxx</implementation>
    </RealWxController>
    <SGEventMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/structure/event_mgr.hxx</declaration>
      <implementation>simgear/structure/event_mgr.cxx</implementation>
    </SGEventMgr>
    <SGInterpolator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/misc/interpolator.hxx</declaration>
      <implementation>simgear/misc/interpolator.cxx</implementation>
    </SGInterpolator>
    <SGPerformanceMonitor>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/structure/SGPerfMon.hxx</declaration>
      <implementation>simgear/structure/SGPerfMon.cxx</implementation>
    </SGPerformanceMonitor>
    <SGSoundMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/sound/soundmgr.hxx</declaration>
    </SGSoundMgr>
    <SGSubsystemMgr>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/structure/subsystem_mgr.hxx</declaration>
      <implementation>simgear/structure/subsystem_mgr.cxx</implementation>
    </SGSubsystemMgr>
    <SGTerraSync>
      <inheritance>SGSubsystem</inheritance>
      <declaration>simgear/scene/tsync/terrasync.hxx</declaration>
      <implementation>simgear/scene/tsync/terrasync.cxx</implementation>
    </SGTerraSync>
    <SlipSkidBall>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/slip_skid_ball.hxx</declaration>
      <implementation>src/Instrumentation/slip_skid_ball.cxx</implementation>
    </SlipSkidBall>
    <StaticSystem>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Systems/static.hxx</declaration>
      <implementation>src/Systems/static.cxx</implementation>
    </StaticSystem>
    <TACAN>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/tacan.hxx</declaration>
      <implementation>src/Instrumentation/tacan.cxx</implementation>
    </TACAN>
    <TCAS>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/tcas.hxx</declaration>
      <implementation>src/Instrumentation/tcas.cxx</implementation>
    </TCAS>
    <TimeManager>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Time/TimeManager.hxx</declaration>
      <implementation>src/Time/TimeManager.cxx</implementation>
    </TimeManager>
    <Transponder>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/transponder.hxx</declaration>
      <implementation>src/Instrumentation/transponder.cxx</implementation>
    </Transponder>
    <TurnIndicator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/turn_indicator.hxx</declaration>
      <implementation>src/Instrumentation/turn_indicator.cxx</implementation>
    </TurnIndicator>
    <VacuumSystem>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Systems/vacuum.hxx</declaration>
      <implementation>src/Systems/vacuum.cxx</implementation>
    </VacuumSystem>
    <VerticalSpeedIndicator>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Instrumentation/vertical_speed_indicator.hxx</declaration>
      <implementation>src/Instrumentation/vertical_speed_indicator.cxx</implementation>
    </VerticalSpeedIndicator>
    <View>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Viewer/view.hxx</declaration>
      <implementation>src/Viewer/view.cxx</implementation>
    </View>
    <wxRadarBg>
      <inheritance>SGSubsystem</inheritance>
      <declaration>src/Cockpit/wxradar.hxx</declaration>
      <implementation>src/Cockpit/wxradar.cxx</implementation>
    </wxRadarBg>
  </primary_subsystems>
  <primary_groups count="8">
    <Autopilot>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Autopilot/autopilot.hxx</declaration>
      <implementation>src/Autopilot/autopilot.cxx</implementation>
    </Autopilot>
    <CockpitDisplayManager>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Cockpit/cockpitDisplayManager.hxx</declaration>
      <implementation>src/Cockpit/cockpitDisplayManager.cxx</implementation>
    </CockpitDisplayManager>
    <FGEnvironmentMgr>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Environment/environment_mgr.hxx</declaration>
      <implementation>src/Environment/environment_mgr.cxx</implementation>
    </FGEnvironmentMgr>
    <FGInput>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Input/input.hxx</declaration>
      <implementation>src/Input/input.cxx</implementation>
    </FGInput>
    <FGInstrumentMgr>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Instrumentation/instrument_mgr.hxx</declaration>
      <implementation>src/Instrumentation/instrument_mgr.cxx</implementation>
    </FGInstrumentMgr>
    <FGSystemMgr>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Systems/system_mgr.hxx</declaration>
      <implementation>src/Systems/system_mgr.cxx</implementation>
    </FGSystemMgr>
    <FGXMLAutopilotGroup>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Autopilot/autopilotgroup.hxx</declaration>
      <implementation>src/Autopilot/autopilotgroup.cxx</implementation>
    </FGXMLAutopilotGroup>
    <TerrainSampler>
      <inheritance>SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Environment/terrainsampler.hxx</declaration>
    </TerrainSampler>
  </primary_groups>
  <secondary_subsystems count="28">
    <AnalogComponent>
      <inheritance>Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/analogcomponent.hxx</declaration>
      <implementation>src/Autopilot/analogcomponent.cxx</implementation>
    </AnalogComponent>
    <BasicRealWxController>
      <inheritance>RealWxController : SGSubsystem</inheritance>
      <declaration>src/Environment/realwx_ctrl.cxx</declaration>
      <implementation>src/Environment/realwx_ctrl.cxx</implementation>
    </BasicRealWxController>
    <CanvasMgr>
      <inheritance>PropertyBasedMgr : SGSubsystem</inheritance>
      <declaration>simgear/canvas/CanvasMgr.hxx</declaration>
      <implementation>simgear/canvas/CanvasMgr.cxx</implementation>
    </CanvasMgr>
    <CommRadioImpl>
      <inheritance>CommRadio : SGSubsystem</inheritance>
      <declaration>src/Instrumentation/commradio.cxx</declaration>
      <implementation>src/Instrumentation/commradio.cxx</implementation>
    </CommRadioImpl>
    <DigitalComponent>
      <inheritance>Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/digitalcomponent.hxx</declaration>
      <implementation>src/Autopilot/digitalcomponent.cxx</implementation>
    </DigitalComponent>
    <FGACMS>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/SP/ACMS.hxx</declaration>
      <implementation>src/FDM/SP/ACMS.cxx</implementation>
    </FGACMS>
    <FGADA>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/SP/ADA.hxx</declaration>
      <implementation>src/FDM/SP/ADA.cxx</implementation>
    </FGADA>
    <FGAISim>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/SP/AISim.hpp</declaration>
      <implementation>src/FDM/SP/AISim.cpp</implementation>
    </FGAISim>
    <FGBalloonSim>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/SP/Balloon.h</declaration>
      <implementation>src/FDM/SP/Balloon.cxx</implementation>
    </FGBalloonSim>
    <FGExternalNet>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/ExternalNet/ExternalNet.hxx</declaration>
      <implementation>src/FDM/ExternalNet/ExternalNet.cxx</implementation>
    </FGExternalNet>
    <FGExternalPipe>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/ExternalPipe/ExternalPipe.hxx</declaration>
      <implementation>src/FDM/ExternalPipe/ExternalPipe.cxx</implementation>
    </FGExternalPipe>
    <FGHIDEventInput>
      <inheritance>FGEventInput : SGSubsystem</inheritance>
      <declaration>src/Input/FGHIDEventInput.hxx</declaration>
      <implementation>src/Input/FGHIDEventInput.cxx</implementation>
    </FGHIDEventInput>
    <FGJSBsim>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/JSBSim/JSBSim.hxx</declaration>
      <implementation>src/FDM/JSBSim/JSBSim.cxx</implementation>
    </FGJSBsim>
    <FGLaRCsim>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/LaRCsim/LaRCsim.hxx</declaration>
      <implementation>src/FDM/LaRCsim/LaRCsim.cxx</implementation>
    </FGLaRCsim>
    <FGLinuxEventInput>
      <inheritance>FGEventInput : SGSubsystem</inheritance>
      <declaration>src/Input/FGLinuxEventInput.hxx</declaration>
      <implementation>src/Input/FGLinuxEventInput.cxx</implementation>
    </FGLinuxEventInput>
    <FGMacOSXEventInput>
      <inheritance>FGEventInput : SGSubsystem</inheritance>
      <declaration>src/Input/FGMacOSXEventInput.hxx</declaration>
      <implementation>src/Input/FGMacOSXEventInput.cxx</implementation>
    </FGMacOSXEventInput>
    <FGMagicCarpet>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/SP/MagicCarpet.hxx</declaration>
      <implementation>src/FDM/SP/MagicCarpet.cxx</implementation>
    </FGMagicCarpet>
    <FGNullFDM>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/NullFDM.hxx</declaration>
      <implementation>src/FDM/NullFDM.cxx</implementation>
    </FGNullFDM>
    <FGReadablePanel>
      <inheritance>FGPanel : SGSubsystem</inheritance>
      <declaration>utils/fgpanel/panel_io.hxx</declaration>
      <implementation>utils/fgpanel/panel_io.cxx</implementation>
    </FGReadablePanel>
    <FGSoundManager>
      <inheritance>SGSoundMgr : SGSubsystem</inheritance>
      <declaration>src/Sound/soundmanager.hxx</declaration>
      <implementation>src/Sound/soundmanager.cxx</implementation>
    </FGSoundManager>
    <FGUFO>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/UFO.hxx</declaration>
      <implementation>src/FDM/UFO.cxx</implementation>
    </FGUFO>
    <KLN89>
      <inheritance>DCLGPS : SGSubsystem</inheritance>
      <declaration>src/Instrumentation/KLN89/kln89.hxx</declaration>
      <implementation>src/Instrumentation/KLN89/kln89.cxx</implementation>
    </KLN89>
    <LayerInterpolateControllerImplementation>
      <inheritance>LayerInterpolateController : SGSubsystem</inheritance>
      <declaration>src/Environment/environment_ctrl.cxx</declaration>
      <implementation>src/Environment/environment_ctrl.cxx</implementation>
    </LayerInterpolateControllerImplementation>
    <MongooseHttpd>
      <inheritance>FGHttpd : SGSubsystem</inheritance>
      <declaration>src/Network/http/httpd.cxx</declaration>
      <implementation>src/Network/http/httpd.cxx</implementation>
    </MongooseHttpd>
    <NavRadioImpl>
      <inheritance>NavRadio : SGSubsystem</inheritance>
      <declaration>src/Instrumentation/newnavradio.cxx</declaration>
      <implementation>src/Instrumentation/newnavradio.cxx</implementation>
    </NavRadioImpl>
    <StateMachineComponent>
      <inheritance>Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/autopilot.cxx</declaration>
      <implementation>src/Autopilot/autopilot.cxx</implementation>
    </StateMachineComponent>
    <YASim>
      <inheritance>FGInterface : SGSubsystem</inheritance>
      <declaration>src/FDM/YASim/YASim.hxx</declaration>
      <implementation>src/FDM/YASim/YASim.cxx</implementation>
    </YASim>
    <agRadar>
      <inheritance>wxRadarBg : SGSubsystem</inheritance>
      <declaration>src/Cockpit/agradar.hxx</declaration>
      <implementation>src/Cockpit/agradar.cxx</implementation>
    </agRadar>
  </secondary_subsystems>
  <secondary_groups count="2">
    <FGXMLAutopilotGroupImplementation>
      <inheritance>FGXMLAutopilotGroup : SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Autopilot/autopilotgroup.cxx</declaration>
      <implementation>src/Autopilot/autopilotgroup.cxx</implementation>
    </FGXMLAutopilotGroupImplementation>
    <TerrainSamplerImplementation>
      <inheritance>TerrainSampler : SGSubsystemGroup : SGSubsystem</inheritance>
      <declaration>src/Environment/terrainsampler.cxx</declaration>
      <implementation>src/Environment/terrainsampler.cxx</implementation>
    </TerrainSamplerImplementation>
  </secondary_groups>
  <tertiary_subsystems count="6">
    <DigitalFilter>
      <inheritance>AnalogComponent : Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/digitalfilter.hxx</declaration>
      <implementation>src/Autopilot/digitalfilter.cxx</implementation>
    </DigitalFilter>
    <Logic>
      <inheritance>DigitalComponent : Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/logic.hxx</declaration>
      <implementation>src/Autopilot/logic.cxx</implementation>
    </Logic>
    <NoaaMetarRealWxController>
      <inheritance>BasicRealWxController : RealWxController : SGSubsystem</inheritance>
      <declaration>src/Environment/realwx_ctrl.cxx</declaration>
      <implementation>src/Environment/realwx_ctrl.cxx</implementation>
    </NoaaMetarRealWxController>
    <PIDController>
      <inheritance>AnalogComponent : Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/pidcontroller.hxx</declaration>
      <implementation>src/Autopilot/pidcontroller.cxx</implementation>
    </PIDController>
    <PISimpleController>
      <inheritance>AnalogComponent : Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/pisimplecontroller.hxx</declaration>
      <implementation>src/Autopilot/pisimplecontroller.cxx</implementation>
    </PISimpleController>
    <Predictor>
      <inheritance>AnalogComponent : Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/predictor.hxx</declaration>
      <implementation>src/Autopilot/predictor.cxx</implementation>
    </Predictor>
  </tertiary_subsystems>
  <quaternary_subsystems count="1">
    <FlipFlop>
      <inheritance>Logic : DigitalComponent : Component : SGSubsystem</inheritance>
      <declaration>src/Autopilot/flipflop.hxx</declaration>
      <implementation>src/Autopilot/flipflop.cxx</implementation>
    </FlipFlop>
  </quaternary_subsystems>
  <counts>
    <simgear>
      <subsystem_classes>9</subsystem_classes>
      <subsystem_groups>0</subsystem_groups>
      <total>9</total>
    </simgear>
    <flightgear>
      <subsystem_classes>117</subsystem_classes>
      <subsystem_groups>10</subsystem_groups>
      <total>127</total>
    </flightgear>
    <combined>
      <subsystem_classes>126</subsystem_classes>
      <subsystem_groups>10</subsystem_groups>
      <total>136</total>
    </combined>
  </counts>
</subsystems>

Refactoring

To check that all subsystems on a branch have been updated or refactored:

Python script: Python script verifying if all subsystems have been updated.

#! /usr/bin/env python3

# Python module imports.
from subprocess import PIPE, Popen

# Other module imports.
from find_subsystems import FindSubsystems


# Source code repository paths.
SIMGEAR_PATH = "/flightgear/src/flightgear-simgear"
FLIGHTGEAR_PATH = "/flightgear/src/flightgear-flightgear"


class ToUpdate:
    """Class for finding all files yet to be updated."""

    def __init__(self):
        """Find all files to be updated."""

        # First find all subsystems.
        subsystems = FindSubsystems()

        # Generate a list of files to skip.
        cmd = "cd %s;" % SIMGEAR_PATH
        cmd += "git diff --name-only ..next;"
        cmd += "cd %s;" % FLIGHTGEAR_PATH
        cmd += "git diff --name-only ..next"
        pipe = Popen(cmd, shell=True, stdout=PIPE)
        blacklist = []
        for line in pipe.stdout.readlines():
            file_name = line.decode()
            file_name = file_name.strip()
            blacklist.append(file_name)

        # Loop over all derived classes.
        print("\nYet to be updated:")
        for storage_list in subsystems.subsystems + subsystems.groups:
            for subsystem in storage_list:
                if subsystem.file_name not in blacklist:
                    print("    %s: %s" % (subsystem.file_name, subsystem))



# Instantiate the class if run as a script.
if __name__ == "__main__":
    ToUpdate()