ArduCopter 3.6.3編譯過程

waf編譯器取代make編譯器

根據ardupilot/BUILD.md

Ardupilot is gradually moving from the make-based build system to
[Waf](https://waf.io/). The instructions below should be enough for you to
build Ardupilot, but you can also read more about the build system in the
[Waf Book](https://waf.io/book/). //ArduPilot逐漸由make編譯轉向Waf編譯，具體指導見https://waf.io/book/

Waf should always be called from the ardupilot's root directory. Differently
from the make-based build, with Waf there's a configure step to choose the
board to be used (default is `sitl`). //waf編譯命令應在"ardupilot/"根目錄下，與make編譯不同，而且waf第一步是configure命令，選擇硬件板類型，默認硬件板是sitl。

硬件Pixracer，固件ArduCopter，waf編譯命令如下：
cd ardupilot
./waf configure --board fmuv4
./waf copter

waf help使用

waf [commands] [options]
commands:

options:

–out=OUT,設置build文件放置在"ardupilot/OUT/"目錄下


–debug: 單步打印編譯過程信息


–upload: 上傳固件至硬件板

waf體系

ardupilot目錄下，waf.py、wscript.py 腳本；
ardupilot各級子目錄下，都有 wscript.py 腳本；
ardupilot/modules/waf：waf編譯器源碼；
ardupilot/Tools/ardupilotwaf:

1. 配置Pixracer編譯環境：
   
   問題是：waf是從哪裏開始啓動的？
   系統最先執行ardupilot/waf.py腳本，直至語句“subprocess.check_call([python,waf_light] + sys.argv[1:])”，該語句啓動了多進程，調用其他腳本，例如“ardupilot/wscript.py”。
   調試發現：
   waf.py啓動了wscript.py腳本，wscript.py接連啓動了Tools/ardupilotwaf/ardupilotwaf.py和boards.py腳本。
   進程結束爲最後時刻。

打開ardupilot/wscript.py:

#!/usr/bin/env python
# encoding: utf-8

from __future__ import print_function

import os.path
import sys
sys.path.insert(0, 'Tools/ardupilotwaf/') //sys.path強制插入系統路徑“Tools/ardupilotwaf/”

import ardupilotwaf //導入Tools/ardupilotwaf/ardupilotwaf.py腳本
import boards      //導入Tools/ardupilotwaf/boards.py腳本

from waflib import Build, ConfigSet, Configure, Context, Utils
//從modules/waf/waflib導入Build.py、ConfigSet.py、Configure.py、Context.py、Utils.py腳本

# TODO: implement a command 'waf help' that shows the basic tasks a
# developer might want to do: e.g. how to configure a board, compile a
# vehicle, compile all the examples, add a new example. Should fit in
# less than a terminal screen, ideally commands should be copy
# pastable. Add the 'export waf="$PWD/waf"' trick to be copy-pastable
# as well.

# TODO: replace defines with the use of the generated ap_config.h file
# this makes recompilation at least when defines change. which might
# be sufficient.

# Default installation prefix for Linux boards
default_prefix = '/usr/'

# Override Build execute and Configure post_recurse methods for autoconfigure purposes
Build.BuildContext.execute = ardupilotwaf.ap_autoconfigure(Build.BuildContext.execute)
Configure.ConfigurationContext.post_recurse = ardupilotwaf.ap_configure_post_recurse()


def _set_build_context_variant(board):
    for c in Context.classes:
        if not issubclass(c, Build.BuildContext):
            continue
        c.variant = board

def init(ctx):
    env = ConfigSet.ConfigSet()
    try:
        p = os.path.join(Context.out_dir, Build.CACHE_DIR, Build.CACHE_SUFFIX)
        env.load(p)
    except EnvironmentError:
        return

    Configure.autoconfig = 'clobber' if env.AUTOCONFIG else False

    board = ctx.options.board or env.BOARD

    if not board:
        return

    # define the variant build commands according to the board
    _set_build_context_variant(board)

def options(opt):
    opt.load('compiler_cxx compiler_c waf_unit_test python')
    opt.load('ardupilotwaf')
    opt.load('build_summary')

    g = opt.ap_groups['configure']

    boards_names = boards.get_boards_names()
    g.add_option('--board',
        action='store',
        choices=boards_names,
        default=None,
        help='Target board to build, choices are %s.' % ', '.join(boards_names))

    g.add_option('--debug',
        action='store_true',
        default=False,
        help='Configure as debug variant.')

    g.add_option('--disable-gccdeps',
        action='store_true',
        default=False,
        help='Disable the use of GCC dependencies output method and use waf default method.')

    g.add_option('--enable-asserts',
        action='store_true',
        default=False,
        help='enable OS level asserts.')

    g.add_option('--use-nuttx-iofw',
        action='store_true',
        default=False,
        help='use old NuttX IO firmware for IOMCU')

    g.add_option('--bootloader',
        action='store_true',
        default=False,
        help='Configure for building a bootloader.')

    g.add_option('--no-autoconfig',
        dest='autoconfig',
        action='store_false',
        default=True,
        help='''Disable autoconfiguration feature. By default, the build system
triggers a reconfiguration whenever it thinks it's necessary - this
option disables that.
''')

    g.add_option('--no-submodule-update',
        dest='submodule_update',
        action='store_false',
        default=True,
        help='''Don't update git submodules. Useful for building with
submodules at specific revisions.
''')

    g.add_option('--enable-header-checks', action='store_true',
        default=False,
        help="Enable checking of headers")

    g.add_option('--default-parameters',
        default=None,
        help='set default parameters to embed in the firmware')

    g.add_option('--enable-math-check-indexes',
                 action='store_true',
                 default=False,
                 help="Enable checking of math indexes")

    g.add_option('--enable-scripting', action='store_true',
                 default=False,
                 help="Enable onboard scripting engine")

    g.add_option('--scripting-checks', action='store_true',
                 default=True,
                 help="Enable runtime scripting sanity checks")

    g = opt.ap_groups['linux']

    linux_options = ('--prefix', '--destdir', '--bindir', '--libdir')
    for k in linux_options:
        option = opt.parser.get_option(k)
        if option:
            opt.parser.remove_option(k)
            g.add_option(option)

    g.add_option('--apstatedir',
        action='store',
        default='',
        help='''Where to save data like parameters, log and terrain.
This is the --localstatedir + ArduPilots subdirectory [default:
board-dependent, usually /var/lib/ardupilot]''')

    g.add_option('--rsync-dest',
        dest='rsync_dest',
        action='store',
        default='',
        help='''Destination for the rsync Waf command. It can be passed during
configuration in order to save typing.
''')

    g.add_option('--enable-benchmarks',
        action='store_true',
        default=False,
        help='Enable benchmarks.')

    g.add_option('--enable-lttng', action='store_true',
        default=False,
        help="Enable lttng integration")

    g.add_option('--disable-libiio', action='store_true',
        default=False,
        help="Don't use libiio even if supported by board and dependencies available")

    g.add_option('--disable-tests', action='store_true',
        default=False,
        help="Disable compilation and test execution")

    g.add_option('--enable-sfml', action='store_true',
                 default=False,
                 help="Enable SFML graphics library")

    g.add_option('--static',
        action='store_true',
        default=False,
        help='Force a static build')

def _collect_autoconfig_files(cfg):
    for m in sys.modules.values():
        paths = []
        if hasattr(m, '__file__') and m.__file__ is not None:
            paths.append(m.__file__)
        elif hasattr(m, '__path__'):
            for p in m.__path__:
                if p is not None:
                    paths.append(p)

        for p in paths:
            if p in cfg.files or not os.path.isfile(p):
                continue

            with open(p, 'rb') as f:
                cfg.hash = Utils.h_list((cfg.hash, f.read()))
                cfg.files.append(p)

def configure(cfg):
    if cfg.options.board is None:
        cfg.options.board = 'sitl'

    cfg.env.BOARD = cfg.options.board
    cfg.env.AUTOCONFIG = cfg.options.autoconfig

    _set_build_context_variant(cfg.env.BOARD)
    cfg.setenv(cfg.env.BOARD)

    cfg.env.BOARD = cfg.options.board
    cfg.env.DEBUG = cfg.options.debug
    cfg.env.ENABLE_ASSERTS = cfg.options.enable_asserts
    cfg.env.BOOTLOADER = cfg.options.bootloader
    cfg.env.USE_NUTTX_IOFW = cfg.options.use_nuttx_iofw

    cfg.env.OPTIONS = cfg.options.__dict__

    # Allow to differentiate our build from the make build
    cfg.define('WAF_BUILD', 1)

    cfg.msg('Autoconfiguration', 'enabled' if cfg.options.autoconfig else 'disabled')

    if cfg.options.static:
        cfg.msg('Using static linking', 'yes', color='YELLOW')
        cfg.env.STATIC_LINKING = True

    cfg.load('ap_library')

    cfg.msg('Setting board to', cfg.options.board)
    cfg.get_board().configure(cfg)

    cfg.load('clang_compilation_database')
    cfg.load('waf_unit_test')
    cfg.load('mavgen')
    cfg.load('uavcangen')

    cfg.env.SUBMODULE_UPDATE = cfg.options.submodule_update

    cfg.start_msg('Source is git repository')
    if cfg.srcnode.find_node('.git'):
        cfg.end_msg('yes')
    else:
        cfg.end_msg('no')
        cfg.env.SUBMODULE_UPDATE = False

    cfg.msg('Update submodules', 'yes' if cfg.env.SUBMODULE_UPDATE else 'no')
    cfg.load('git_submodule')

    if cfg.options.enable_benchmarks:
        cfg.load('gbenchmark')
    cfg.load('gtest')
    cfg.load('static_linking')
    cfg.load('build_summary')

    cfg.start_msg('Benchmarks')
    if cfg.env.HAS_GBENCHMARK:
        cfg.end_msg('enabled')
    else:
        cfg.end_msg('disabled', color='YELLOW')

    cfg.start_msg('Unit tests')
    if cfg.env.HAS_GTEST:
        cfg.end_msg('enabled')
    else:
        cfg.end_msg('disabled', color='YELLOW')

    cfg.start_msg('Scripting')
    if cfg.options.enable_scripting:
        cfg.end_msg('enabled')
    else:
        cfg.end_msg('disabled', color='YELLOW')

    cfg.start_msg('Scripting runtime checks')
    if cfg.options.scripting_checks:
        cfg.end_msg('enabled')
    else:
        cfg.end_msg('disabled', color='YELLOW')

    cfg.env.append_value('GIT_SUBMODULES', 'mavlink')

    cfg.env.prepend_value('INCLUDES', [
        cfg.srcnode.abspath() + '/libraries/',
    ])

    cfg.find_program('rsync', mandatory=False)
    if cfg.options.rsync_dest:
        cfg.msg('Setting rsync destination to', cfg.options.rsync_dest)
        cfg.env.RSYNC_DEST = cfg.options.rsync_dest

    if cfg.options.enable_header_checks:
        cfg.msg('Enabling header checks', cfg.options.enable_header_checks)
        cfg.env.ENABLE_HEADER_CHECKS = True
    else:
        cfg.env.ENABLE_HEADER_CHECKS = False

    # TODO: Investigate if code could be changed to not depend on the
    # source absolute path.
    cfg.env.prepend_value('DEFINES', [
        'SKETCHBOOK="' + cfg.srcnode.abspath() + '"',
    ])

    # Always use system extensions
    cfg.define('_GNU_SOURCE', 1)

    cfg.write_config_header(os.path.join(cfg.variant, 'ap_config.h'))

    _collect_autoconfig_files(cfg)

def collect_dirs_to_recurse(bld, globs, **kw):
    dirs = []
    globs = Utils.to_list(globs)

    if bld.bldnode.is_child_of(bld.srcnode):
        kw['excl'] = Utils.to_list(kw.get('excl', []))
        kw['excl'].append(bld.bldnode.path_from(bld.srcnode))

    for g in globs:
        for d in bld.srcnode.ant_glob(g + '/wscript', **kw):
            dirs.append(d.parent.relpath())
    return dirs

def list_boards(ctx):
    print(*boards.get_boards_names())

def board(ctx):
    env = ConfigSet.ConfigSet()
    try:
        p = os.path.join(Context.out_dir, Build.CACHE_DIR, Build.CACHE_SUFFIX)
        env.load(p)
    except:
        print('No board currently configured')
        return

    print('Board configured to: {}'.format(env.BOARD))

def _build_cmd_tweaks(bld):
    if bld.cmd == 'check-all':
        bld.options.all_tests = True
        bld.cmd = 'check'

    if bld.cmd == 'check':
        if not bld.env.HAS_GTEST:
            bld.fatal('check: gtest library is required')
        bld.options.clear_failed_tests = True

def _build_dynamic_sources(bld):
    if not bld.env.BOOTLOADER:
        bld(
            features='mavgen',
            source='modules/mavlink/message_definitions/v1.0/ardupilotmega.xml',
            output_dir='libraries/GCS_MAVLink/include/mavlink/v2.0/',
            name='mavlink',
            # this below is not ideal, mavgen tool should set this, but that's not
            # currently possible
            export_includes=[
            bld.bldnode.make_node('libraries').abspath(),
            bld.bldnode.make_node('libraries/GCS_MAVLink').abspath(),
            ],
            )

    if bld.get_board().with_uavcan or bld.env.HAL_WITH_UAVCAN==True:
        bld(
            features='uavcangen',
            source=bld.srcnode.ant_glob('modules/uavcan/dsdl/uavcan/**/*.uavcan'),
            output_dir='modules/uavcan/libuavcan/include/dsdlc_generated',
            name='uavcan',
            export_includes=[
                bld.bldnode.make_node('modules/uavcan/libuavcan/include/dsdlc_generated').abspath(),
            ]
        )

    def write_version_header(tsk):
        bld = tsk.generator.bld
        return bld.write_version_header(tsk.outputs[0].abspath())

    bld(
        name='ap_version',
        target='ap_version.h',
        vars=['AP_VERSION_ITEMS'],
        rule=write_version_header,
    )

    bld.env.prepend_value('INCLUDES', [
        bld.bldnode.abspath(),
    ])

def _build_common_taskgens(bld):
    # NOTE: Static library with vehicle set to UNKNOWN, shared by all
    # the tools and examples. This is the first step until the
    # dependency on the vehicles is reduced. Later we may consider
    # split into smaller pieces with well defined boundaries.
    bld.ap_stlib(
        name='ap',
        ap_vehicle='UNKNOWN',
        ap_libraries=bld.ap_get_all_libraries(),
    )

    if bld.env.HAS_GTEST:
        bld.libgtest(cxxflags=['-include', 'ap_config.h'])

    if bld.env.HAS_GBENCHMARK:
        bld.libbenchmark()

def _build_recursion(bld):
    common_dirs_patterns = [
        # TODO: Currently each vehicle also generate its own copy of the
        # libraries. Fix this, or at least reduce the amount of
        # vehicle-dependent libraries.
        '*',
        'Tools/*',
        'libraries/*/examples/*',
        'libraries/*/tests',
        'libraries/*/utility/tests',
        'libraries/*/benchmarks',
    ]

    common_dirs_excl = [
        'modules',
        'libraries/AP_HAL_*',
        'libraries/SITL',
    ]

    hal_dirs_patterns = [
        'libraries/%s/tests',
        'libraries/%s/*/tests',
        'libraries/%s/*/benchmarks',
        'libraries/%s/examples/*',
    ]

    dirs_to_recurse = collect_dirs_to_recurse(
        bld,
        common_dirs_patterns,
        excl=common_dirs_excl,
    )
    if bld.env.IOMCU_FW is not None:
        if bld.env.IOMCU_FW:
            dirs_to_recurse.append('libraries/AP_IOMCU/iofirmware')
    for p in hal_dirs_patterns:
        dirs_to_recurse += collect_dirs_to_recurse(
            bld,
            [p % l for l in bld.env.AP_LIBRARIES],
        )

    # NOTE: we need to sort to ensure the repeated sources get the
    # same index, and random ordering of the filesystem doesn't cause
    # recompilation.
    dirs_to_recurse.sort()

    for d in dirs_to_recurse:
        bld.recurse(d)

def _build_post_funs(bld):
    if bld.cmd == 'check':
        bld.add_post_fun(ardupilotwaf.test_summary)
    else:
        bld.build_summary_post_fun()

    if bld.env.SUBMODULE_UPDATE:
        bld.git_submodule_post_fun()

def _load_pre_build(bld):
    '''allow for a pre_build() function in build modules'''
    brd = bld.get_board()
    if getattr(brd, 'pre_build', None):
        brd.pre_build(bld)    

def build(bld):
    config_hash = Utils.h_file(bld.bldnode.make_node('ap_config.h').abspath())
    bld.env.CCDEPS = config_hash
    bld.env.CXXDEPS = config_hash

    bld.post_mode = Build.POST_LAZY

    bld.load('ardupilotwaf')

    bld.env.AP_LIBRARIES_OBJECTS_KW.update(
        use=['mavlink'],
        cxxflags=['-include', 'ap_config.h'],
    )

    _load_pre_build(bld)

    if bld.get_board().with_uavcan:
        bld.env.AP_LIBRARIES_OBJECTS_KW['use'] += ['uavcan']

    _build_cmd_tweaks(bld)

    if bld.env.SUBMODULE_UPDATE:
        bld.add_group('git_submodules')
        for name in bld.env.GIT_SUBMODULES:
            bld.git_submodule(name)

    bld.add_group('dynamic_sources')
    _build_dynamic_sources(bld)

    bld.add_group('build')
    bld.get_board().build(bld)
    _build_common_taskgens(bld)

    _build_recursion(bld)

    _build_post_funs(bld)

ardupilotwaf.build_command('check',
    program_group_list='all',
    doc='builds all programs and run tests',
)
ardupilotwaf.build_command('check-all',
    program_group_list='all',
    doc='shortcut for `waf check --alltests`',
)

for name in ('antennatracker', 'copter', 'heli', 'plane', 'rover', 'sub', 'bootloader','iofirmware'):
    ardupilotwaf.build_command(name,
        program_group_list=name,
        doc='builds %s programs' % name,
    )

for program_group in ('all', 'bin', 'tools', 'examples', 'tests', 'benchmarks'):
    ardupilotwaf.build_command(program_group,
        program_group_list=program_group,
        doc='builds all programs of %s group' % program_group,
    )

class LocalInstallContext(Build.InstallContext):
    """runs install using BLD/install as destdir, where BLD is the build variant directory"""
    cmd = 'localinstall'

    def __init__(self, **kw):
        super(LocalInstallContext, self).__init__(**kw)
        self.local_destdir = os.path.join(self.variant_dir, 'install')

    def execute(self):
        old_destdir = self.options.destdir
        self.options.destdir = self.local_destdir
        r = super(LocalInstallContext, self).execute()
        self.options.destdir = old_destdir
        return r

class RsyncContext(LocalInstallContext):
    """runs localinstall and then rsyncs BLD/install with the target system"""
    cmd = 'rsync'

    def __init__(self, **kw):
        super(RsyncContext, self).__init__(**kw)
        self.add_pre_fun(RsyncContext.create_rsync_taskgen)

    def create_rsync_taskgen(self):
        if 'RSYNC' not in self.env:
            self.fatal('rsync program seems not to be installed, can\'t continue')

        self.add_group()

        tg = self(
            name='rsync',
            rule='${RSYNC} -a ${RSYNC_SRC}/ ${RSYNC_DEST}',
            always=True,
        )

        tg.env.RSYNC_SRC = self.local_destdir
        if self.options.rsync_dest:
            self.env.RSYNC_DEST = self.options.rsync_dest

        if 'RSYNC_DEST' not in tg.env:
            self.fatal('Destination for rsync not defined. Either pass --rsync-dest here or during configuration.')

        tg.post()

Tools/ardupilotwaf/ardupilotwaf.py腳本