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Signed-off-by: BigfootACA <bigfoot@classfun.cn>

builder/build/fstab.py

@@ -6,41 +6,75 @@ log = getLogger(__name__)
 
 
 def write_fstab(ctx: ArchBuilderContext):
+	"""
+	Generate fstab and write to rootfs
+	"""
 	log.debug(
 		"generate fstab:\n\t%s",
 		ctx.fstab.to_mount_file("\n\t").strip()
 	)
+	# WORKSPACE/TARGET/rootfs/etc/fstab
 	path = os.path.join(ctx.get_rootfs(), "etc/fstab")
 	with open_config(path) as f:
 		ctx.fstab.write_mount_file(f)
 
 
 def mount_all(ctx: ArchBuilderContext):
+	"""
+	Mount all filesystems in fstab for build
+	"""
 	path = ctx.get_mount()
 	root = ctx.get_rootfs()
+
+	# ensure WORKSPACE/TARGET/mount is existing
 	if not os.path.exists(path):
 		os.mkdir(path, mode=0o0755)
+
+	# the first item must be ROOT (sorted by ctx.fstab.resort())
 	if ctx.fstab[0].target != "/":
 		raise RuntimeError("no root to mount")
+
 	for mnt in ctx.fstab:
+		# do not change original item
 		m = mnt.clone()
+
+		# skip virtual source device
 		if m.source == "none": continue
+
+		# we should mount virtual device
+		# original: /dev/mmcblk0p1, PARTLABEL=linux
+		# we need: /dev/loop0, /dev/loop1
+		# see builder.disk.filesystem.build.FileSystemBuilder.proc_fstab()
 		if m.source not in ctx.fsmap:
 			raise RuntimeError(f"source {m.source} cannot map to host")
 		m.source = ctx.fsmap[m.source]
-		if m.target == "/": in_mnt, in_root = path, root
+
+		if m.target == "/":
+			# process ROOT resolve unneeded
+			in_mnt, in_root = path, root
 		elif m.target.startswith("/"):
+			# resolve to ROOT and MOUNT
+			# m.target: /boot
+			# in_mnt: WORKSPACE/TARGET/mount/boot
+			# in_root: WORKSPACE/TARGET/rootfs/boot
 			folder = m.target[1:]
 			in_mnt = os.path.join(path, folder)
 			in_root = os.path.join(root, folder)
-		elif m.fstype == "swap" or m.target == "none": continue
+		elif m.fstype == "swap" or m.target == "none":
+			# skip mount virtual fs and swap
+			continue
 		else: raise RuntimeError(f"target {m.target} cannot map to host")
+
 		if in_mnt:
+			# ensure mount target is exists
 			m.target = in_mnt
 			if not os.path.exists(in_mnt):
 				os.makedirs(in_mnt, mode=0o0755)
 		if in_root and not os.path.exists(in_root):
+			# ensure the folder is also exists in rootfs
 			os.makedirs(in_root, mode=0o0755)
+
+		# invoke real mount
 		m.mount()
 		ctx.mounted.insert(0, m)
 

builder/build/grub.py

@@ -27,6 +27,9 @@ def get_prop(
 	path: bool = False,
 	multi: bool = False,
 ) -> str | None:
+	"""
+	Get a config value for grub
+	"""
 	value = ctx.get(f"kernel.{name}", None)
 	if name in cfg: value = cfg[name]
 	if value is None: return None
@@ -34,6 +37,7 @@ def get_prop(
 		value = [value]
 	if len(value) == 0: return None
 	if path:
+		# must starts with /
 		for i in range(len(value)):
 			if not value[i].startswith("/"):
 				value[i] = "/" + value[i]
@@ -43,6 +47,9 @@ def get_prop(
 
 
 def fstype_to_mod(name: str) -> str:
+	"""
+	Map filesystem type to GRUB2 modules name
+	"""
 	match name:
 		case "ext3": return "ext2"
 		case "ext4": return "ext2"
@@ -51,38 +58,72 @@ def fstype_to_mod(name: str) -> str:
 		case "fat16": return "fat"
 		case "fat32": return "fat"
 		case "msdos": return "fat"
+		# TODO: add more filesystems
 		case _: return name
 
 
 def gen_menuentry(ctx: ArchBuilderContext, cfg: dict) -> str:
+	"""
+	Generate a menuentry config for grub
+	"""
 	ret = ""
+
+	# menuentry name (default to Linux)
 	name = cfg["name"] if "name" in cfg else "Linux"
+
+	# kernel image path
 	kernel = get_prop(ctx, "kernel", cfg, True)
+
+	# initramfs image path (supports multiples)
 	initramfs = get_prop(ctx, "initramfs", cfg, True, True)
+
+	# device tree blob path (supports multiples)
 	devicetree = get_prop(ctx, "devicetree", cfg, True, True)
+
+	# kernel command line
 	cmdline = get_prop(ctx, "cmdline", cfg, False, True)
+
+	# the folder to place these files
 	path = get_prop(ctx, "path", cfg, False, False)
+
 	if kernel is None: raise ArchBuilderConfigError("no kernel for grub")
 	if cmdline is None: cmdline = ""
 	ret += f"menuentry '{name}' {{\n"
+
+	# if path set: load filesystem module and search to set root
 	if path:
+		# find out the mount point in fstab
 		fs = ctx.fstab.find_target(path)
 		if fs is None or len(fs) == 0 or fs[0] is None:
 			raise ArchBuilderConfigError(f"mountpoint {path} not found")
 		dev = fs[0].source
+
+		# map to virtual file system
 		if dev in ctx.fsmap: dev = ctx.fsmap[dev]
+
+		# get the filesystem UUID to search
 		uuid = blkid.get_tag_value(None, "UUID", dev)
 		if uuid is None: raise RuntimeError(f"cannot detect uuid for {path}")
+
+		# load filesystem module and search target
 		ret += "\tinsmod %s\n" % fstype_to_mod(fs[0].fstype)
 		ret += f"\tsearch --no-floppy --fs-uuid --set=root {uuid}\n"
+
+	# add device tree blob field
 	if devicetree:
 		ret += "\techo 'Loading Device Tree...'\n"
 		ret += f"\tdevicetree {devicetree}\n"
+
+	# add kernel path field and kernel command line
 	ret += "\techo 'Loading Kernel...'\n"
 	ret += f"\tlinux {kernel} {cmdline}\n"
+
+	# add initramfs field
 	if initramfs:
 		ret += "\techo 'Loading Initramfs...'\n"
 		ret += f"\tinitrd {initramfs}\n"
+
+	# boot into linux (not add 'boot' command, its imply by menuentry)
 	ret += "\techo 'Booting...'\n"
 	ret += f"}}\n"
 	return ret
@@ -90,18 +131,26 @@ def gen_menuentry(ctx: ArchBuilderContext, cfg: dict) -> str:
 
 def gen_basic(ctx: ArchBuilderContext) -> str:
 	ret = ""
+
+	# load generic modules
 	ret += "insmod part_gpt\n"
 	ret += "insmod part_msdos\n"
 	ret += "insmod all_video\n"
+
+	# setup console and serial
 	ret += "terminal_input console\n"
 	ret += "terminal_output console\n"
 	ret += "if serial --unit=0 --speed=115200; then\n"
 	ret += "\tterminal_input --append console\n"
 	ret += "\tterminal_output --append console\n"
 	ret += "fi\n"
+
+	# set grub timeout seconds
 	ret += "set timeout_style=menu\n"
 	timeout = ctx.get("bootloader.timeout", 5)
 	ret += f"set timeout={timeout}\n"
+
+	# find out the default entry
 	default = 0
 	items = ctx.get("bootloader.items", [])
 	for idx in range(len(items)):
@@ -109,10 +158,14 @@ def gen_basic(ctx: ArchBuilderContext) -> str:
 		if "default" in item and item["default"]:
 			default = idx
 	ret += f"set default={default}\n"
+
 	return ret
 
 
 def mkconfig(ctx: ArchBuilderContext) -> str:
+	"""
+	Generate a full grub config for current rootfs
+	"""
 	ret = ""
 	ret += gen_basic(ctx)
 	for item in ctx.get("bootloader.items", []):
@@ -121,15 +174,23 @@ def mkconfig(ctx: ArchBuilderContext) -> str:
 
 
 def proc_targets(ctx: ArchBuilderContext, install: str):
+	"""
+	Copy grub target folder directly
+	"""
 	copies = [".mod", ".lst"]
 	folder = os.path.join(ctx.get_rootfs(), "usr/lib/grub")
 	for target in ctx.get("grub.targets", []):
+		# target name format: i386-pc, arm64-efi
 		if "/" in target: raise ArchBuilderConfigError(f"bad target {target}")
 		base = os.path.join(folder, target)
+
+		# at least we need linux.mod
 		if not os.path.exists(os.path.join(base, "linux.mod")):
 			raise ArchBuilderConfigError(f"target {target} not found")
 		dest = os.path.join(install, target)
 		os.makedirs(dest, mode=0o0755, exist_ok=True)
+
+		# copy grub target
 		for file in os.listdir(base):
 			if not any((file.endswith(name) for name in copies)):
 				continue
@@ -141,6 +202,9 @@ def proc_targets(ctx: ArchBuilderContext, install: str):
 
 
 def proc_config(ctx: ArchBuilderContext, install: str):
+	"""
+	Generate a full grub config for current rootfs and write to install folder
+	"""
 	content = mkconfig(ctx)
 	cfg = os.path.join(install, "grub.cfg")
 	with open(cfg, "w") as f:
@@ -149,6 +213,9 @@ def proc_config(ctx: ArchBuilderContext, install: str):
 
 
 def efi_arch_name(target: str) -> str:
+	"""
+	Map grub target name to UEFI arch name
+	"""
 	match target:
 		case "arm64-efi": return "aa64"
 		case "x86_64-efi": return "x64"
@@ -161,50 +228,97 @@ def efi_arch_name(target: str) -> str:
 
 
 def efi_boot_name(target: str) -> str:
+	"""
+	Map grub target name to UEFI default boot file name
+	"""
 	name = efi_arch_name(target)
 	return f"boot{name}.efi"
 
 
 def proc_mkimage_efi(ctx: ArchBuilderContext, target: str):
+	"""
+	Create GRUB EFI image for boot
+	"""
 	cmds = ["grub-mkimage"]
 	root = ctx.get_rootfs()
+
+	# allowed esp folders
 	efi_folders = ["/boot", "/boot/efi", "/efi", "/esp"]
+
+	# grub2 source folder in rootfs (WORKSPACE/TARGET/rootfs/usr/lib/grub/x86_64-efi)
 	base = os.path.join(root, "usr/lib/grub", target)
+
+	# install path in rootfs (/boot/grub)
 	install = ctx.get("grub.path", "/boot/grub")
+
+	# why this function called proc_mkimage_efi?
 	if not target.endswith("-efi"):
 		raise RuntimeError("mkimage efi only for *-efi")
-	esp: MountPoint | None = None
-	grub: MountPoint | None = None
-	fdir = install + "/"
+
+	# must ends with /
+	fdir = os.path.realpath(install) + "/"
+
+	# find out requires mount point
+	esp: MountPoint | None = None # UEFI system partition
+	grub: MountPoint | None = None # GRUB install folder
 	for mnt in ctx.fstab:
+		# esp must be fat
 		if fstype_to_mod(mnt.fstype) == "fat":
 			if mnt.target in efi_folders:
 				esp = mnt
+
+		# add an end slash to avoid same prefix (likes /boot /bootfs)
 		tdir = mnt.target
 		if not tdir.endswith("/"): tdir += "/"
+
+		# grub install folder
 		if fdir.startswith(tdir):
+			# find out the deepest mount point
+			# to avoid / but installed in /boot
 			if (not grub) or mnt.level >= grub.level:
 				grub = mnt
-	if esp is None: raise RuntimeError("efi partiton not found")
+	if esp is None: raise RuntimeError("efi partition not found")
 	if grub is None: raise RuntimeError("grub install folder not found")
-	esp_dest = esp.target
-	if esp_dest.startswith("/"): esp_dest = esp_dest[1:]
-	if not install.startswith("/"): install = "/" + install
+
+	# grub install target folder (/boot/grub)
+	if not install.startswith("/"):
+		install = "/" + install
+
+	# must in grub install folder
 	if not install.startswith(grub.target):
 		raise RuntimeError("grub install prefix not found")
+
+	# get grub install path in target partition
+	#  Mount  GRUB Install  Prefix
+	#  /boot  /boot/grub    /grub
+	#  /      /boot/grub    /boot/grub
 	prefix = install[len(grub.target):]
 	if not prefix.startswith("/"): prefix = "/" + prefix
+
+	# get UUID of grub installed filesystem UUID
 	device = (ctx.fsmap[grub.source] if grub.source in ctx.fsmap else grub.source)
 	uuid = blkid.get_tag_value(None, "UUID", device)
 	if not uuid: raise RuntimeError(
 		"failed to detect uuid for grub install path"
 	)
+
+	# esp install target folder (boot/efi)
+	esp_dest = esp.target
+	if esp_dest.startswith("/"):
+		esp_dest = esp_dest[1:]
+
+	# esp install target folder in rootfs (WORKSPACE/TARGET/rootfs/boot/efi)
 	efi_folder = os.path.join(root, esp_dest)
+
+	# grub install target folder in rootfs (WORKSPACE/TARGET/rootfs/boot/grub)
 	grub_folder = os.path.join(root, install[1:])
+
 	cmds.append(f"--format={target}")
 	cmds.append(f"--directory={base}")
 	cmds.append(f"--prefix={prefix}")
 	cmds.append("--compression=xz")
+
+	# put builtin config into grub install folder
 	builtin = os.path.join(grub_folder, "grub.builtin.cfg")
 	with open(builtin, "w") as f:
 		f.write(f"search --no-floppy --fs-uuid --set=root {uuid}\n")
@@ -213,62 +327,98 @@ def proc_mkimage_efi(ctx: ArchBuilderContext, target: str):
 		f.write("echo \"Failed to switch into normal mode\"\n")
 		f.write("sleep 5\n")
 	cmds.append(f"--config={builtin}")
+
+	# efi boot image install folder (WORKSPACE/TARGET/rootfs/boot/efi/efi/boot)
 	efi = os.path.join(efi_folder, "efi/boot")
 	os.makedirs(efi, mode=0o0755, exist_ok=True)
+
+	# efi boot image (WORKSPACE/TARGET/rootfs/boot/efi/efi/boot/bootx64.efi)
 	out = os.path.join(efi, efi_boot_name(target))
 	cmds.append(f"--output={out}")
 	if os.path.exists(out): os.remove(out)
+
 	cmds.extend(modules)
+
+	# run grub-mkimage
 	ret = ctx.run_external(cmds)
 	if ret != 0: raise OSError("grub-mkimage failed")
 	log.info(f"generated grub {target} efi image {out}")
 
 
 def proc_bootsec(ctx: ArchBuilderContext, target: str):
+	"""
+	Install boot sector for x86 PC for grub-install
+	"""
 	mods = []
 	cmds = ["grub-install"]
 	if target != "i386-pc":
 		raise RuntimeError("bootsec only for i386-pc")
 	mount = ctx.get_mount()
 	root = ctx.get_rootfs()
+
+	# get grub install base folder (boot)
 	install: str = ctx.get("grub.path", "/boot/grub")
 	if install.startswith("/"): install = install[1:]
+	if install.endswith("/grub"): install = install[:-5]
+
 	grub = os.path.join(root, "usr/lib/grub", target)
-	if install.endswith("/grub"): install = install[0:-5]
+
 	cmds.append(f"--target={target}")
 	cmds.append(f"--directory={grub}")
+
 	mods.append("part_msdos")
 	mods.append("part_gpt")
-	rootfs = ctx.fstab.find_target("/")
+
+	# grub install base folder in mount (WORKSPACE/TARGET/mount/boot)
 	mnt_install = os.path.join(mount, install)
 	cmds.append(f"--boot-directory={mnt_install}")
+
+	# find out mount point of rootfs
+	rootfs = ctx.fstab.find_target("/")
 	if rootfs is None or len(rootfs) <= 0 or rootfs[0] is None:
 		raise RuntimeError("rootfs mount point not found")
 	rootfs = rootfs[0]
+
+	# add filesystem module for rootfs
 	mods.append(fstype_to_mod(rootfs.fstype))
 	if len(mods) > 0:
 		cmds.append("--modules=" + (" ".join(mods)))
+
+	# detect grub boot sector install device
 	device = ctx.get("grub.device", None)
 	if device is None:
 		source = rootfs.source
 		if source in ctx.fsmap:
 			source = ctx.fsmap[source]
+
+		# loop setup by builder.disk.image.ImageBuilder
 		if not source.startswith("/dev/loop"):
 			raise RuntimeError("no device to detect grub install")
+
+		# loop offset partition setup by builder.disk.layout.build.DiskLayoutBuilder
 		if loop_get_offset(source) <= 0:
 			raise RuntimeError("no loop part to detect grub install")
+
+		# backing as parent disk
 		device = loop_get_backing(source)
 	if device is None:
 		raise RuntimeError("no device for grub install")
 	cmds.append(device)
+
+	# run grub-install
 	ret = ctx.run_external(cmds)
 	if ret != 0: raise OSError("grub-install failed")
+
+	# copy grub installed target from mount to rootfs
 	src = os.path.join(mnt_install, "grub")
 	dst = os.path.join(root, install, "grub")
 	shutil.copytree(src, dst, dirs_exist_ok=True)
 
 
 def proc_install(ctx: ArchBuilderContext):
+	"""
+	Process GRUB targets install
+	"""
 	targets: list[str] = ctx.get("grub.targets", [])
 	for target in targets:
 		if target == "i386-pc":
@@ -281,12 +431,18 @@ def proc_install(ctx: ArchBuilderContext):
 
 
 def proc_grub(ctx: ArchBuilderContext):
+	"""
+	Install GRUB bootloader
+	"""
 	root = ctx.get_rootfs()
+
+	# get grub install folder in rootfs (WORKSPACE/TARGET/rootfs/boot/grub)
 	install: str = ctx.get("grub.path", "/boot/grub")
 	if install.startswith("/"):
 		install = install[1:]
 	install = os.path.join(root, install)
 	os.makedirs(install, mode=0o0755, exist_ok=True)
+
 	proc_config(ctx, install)
 	proc_targets(ctx, install)
 	proc_install(ctx)

builder/build/locale.py

@@ -8,49 +8,77 @@ log = getLogger(__name__)
 
 
 def reset_locale(ctx: ArchBuilderContext):
+	"""
+	Remove old locale settings
+	"""
 	root = ctx.get_rootfs()
 	archive = os.path.join(root, "usr/lib/locale/locale-archive")
 	if os.path.exists(archive): os.remove(archive)
 
 
 def enable_all(ctx: ArchBuilderContext):
+	"""
+	Add all enabled locale for build locale-archive
+	"""
 	root = ctx.get_rootfs()
+
+	# default none
 	locales = ctx.get("locale.enable", [])
 	log.info("setup enabled locale")
+
+	# create locale.gen
 	file = os.path.join(root, "etc/locale.gen")
 	with open_config(file) as f:
 		for line in locales:
 			log.debug(f"adding locale {line}")
 			f.write(line)
-			f.write("\n")
+			f.write(os.linesep)
 		if len(locales) == 0:
 			f.write("# No any locales enabled\n")
+
+	# run locale-gen
 	filesystem.chroot_run(ctx, "locale-gen")
 
 
 def set_default(ctx: ArchBuilderContext):
+	"""
+	Setup default locale
+	"""
 	root = ctx.get_rootfs()
-	default = ctx.get("locale.default", None)
-	if default is None: default = "C"
+
+	# default to C
+	default = ctx.get("locale.default", "C")
 	log.info(f"default locale: {default}")
+
+	# default locale config (see man:locale.conf(5))
 	conf = os.path.join(root, "etc/locale.conf")
 	with open_config(conf) as f:
 		f.write(f"LANG={default}\n")
 
 
 def set_timezone(ctx: ArchBuilderContext):
+	"""
+	Setup tzdata timezone info
+	"""
 	root = ctx.get_rootfs()
-	timezone = ctx.get("timezone", None)
-	if timezone is None: timezone = "UTC"
+
+	# default to UTC
+	timezone = ctx.get("timezone", "UTC")
 	log.info(f"timezone: {timezone}")
+
+	# tzdata install path
 	dst = os.path.join("/usr/share/zoneinfo", timezone)
 	real = os.path.join(root, dst[1:])
 	if not os.path.exists(real): raise ArchBuilderConfigError(
 		f"timezone {timezone} not found"
 	)
+
+	# localtime symbolic link (see man:tzset(3))
 	lnk = os.path.join(root, "etc/localtime")
 	if os.path.exists(lnk): os.remove(lnk)
 	os.symlink(dst, lnk)
+
+	# timezone file
 	conf = os.path.join(root, "etc/timezone")
 	with open(conf, "w") as f:
 		f.write(timezone)
@@ -58,6 +86,9 @@ def set_timezone(ctx: ArchBuilderContext):
 
 
 def proc_locale(ctx: ArchBuilderContext):
+	"""
+	Setup user locale settings
+	"""
 	reset_locale(ctx)
 	enable_all(ctx)
 	set_default(ctx)

builder/build/mkinitcpio.py

@@ -17,22 +17,37 @@ def add_values(ctx: ArchBuilderContext, key: str, arr: list[str]):
 
 
 def gen_config(ctx: ArchBuilderContext):
+	"""
+	Generate mkinitcpio.conf
+	"""
 	modules: list[str] = []
 	binaries: list[str] = []
 	files: list[str] = []
 	hooks: list[str] = []
+
+	# add default hooks
 	hooks.append("base")
 	hooks.append("systemd")
 	hooks.append("autodetect")
+
+	# add microcode if x86_64 (amd-ucode, intel-ucode)
 	if ctx.cur_arch in ["x86_64", "i386"]:
 		hooks.append("microcode")
+
 	hooks.append("modconf")
+
+	# do not add keymap by default
 	if ctx.get("mkinitcpio.hooks.keymap", False):
-		hooks.extend(["kms", "keyboard", "keymap", "consolefont"])
-	hooks.extend(["block", "filesystems", "fsck"])
+		hooks.extend(["kms", "keymap", "consolefont"])
+
+	hooks.extend(["keyboard", "block", "filesystems", "fsck"])
+
+	# add others values
 	add_values(ctx, "mkinitcpio.modules", modules)
 	add_values(ctx, "mkinitcpio.binaries", binaries)
 	add_values(ctx, "mkinitcpio.files", files)
+
+	# write mkinitcpio.conf to rootfs
 	root = ctx.get_rootfs()
 	cfg = os.path.join(root, "etc/mkinitcpio.conf")
 	with open_config(cfg) as f:
@@ -40,27 +55,47 @@ def gen_config(ctx: ArchBuilderContext):
 		f.write("BINARIES=(%s)\n" % (" ".join(binaries)))
 		f.write("FILES=(%s)\n" % (" ".join(files)))
 		f.write("HOOKS=(%s)\n" % (" ".join(hooks)))
+		# TODO: add more options
 
 
 def recreate_initrd(ctx: ArchBuilderContext, path: str):
+	"""
+	Really run mkinitcpio
+	"""
 	chroot_run(ctx, ["mkinitcpio", "-p", path])
+	# do not check return value of mkinitcpio
 
 
 def recreate_initrd_no_autodetect(ctx: ArchBuilderContext, path: str):
+	"""
+	Create a full initramfs without autodetect
+	In build stage, mkinitcpio can not find out needs modules, it will cause unbootable.
+	"""
 	tmp = os.path.join(ctx.get_rootfs(), "tmp")
 	with NamedTemporaryFile("w", dir=tmp) as temp:
+
+		# copy original preset
 		with open(path, "r") as f:
 			temp.write(f.read())
+
+		# skip autodetect
 		temp.write("\ndefault_options=\"-S autodetect\"\n")
 		temp.flush()
+
+		# run mkinitcpio (with path in rootfs)
 		path = os.path.join("/tmp", os.path.basename(temp.name))
 		recreate_initrd(ctx, path)
 
 
 def recreate_initrds(ctx: ArchBuilderContext):
+	"""
+	Regenerate all initramfs
+	"""
 	root = ctx.get_rootfs()
 	no_autodetect = ctx.get("mkinitcpio.no_autodetect", True)
 	folder = os.path.join(root, "etc/mkinitcpio.d")
+
+	# scan all initramfs preset and regenerate them
 	for preset in os.listdir(folder):
 		if not preset.endswith(".preset"): continue
 		path = os.path.join(folder, preset)
@@ -69,5 +104,8 @@ def recreate_initrds(ctx: ArchBuilderContext):
 
 
 def proc_mkinitcpio(ctx: ArchBuilderContext):
+	"""
+	Process mkinitcpio options
+	"""
 	gen_config(ctx)
 	recreate_initrds(ctx)

builder/build/mount.py

@@ -82,9 +82,11 @@ def init_mount(ctx: ArchBuilderContext):
 		real = os.path.realpath(os.path.join(root, target))
 		do_mount(ctx, source, real, fstype, options)
 	try:
+		# ensure mount point is clean
 		mnts = MountTab.parse_mounts()
 		if any(mnts.find_folder(ctx.work)):
 			raise RuntimeError("mount points not cleanup")
+
 		root_mount("proc", "proc", "proc", "nosuid,noexec,nodev")
 		root_mount("sys", "sys", "sysfs", "nosuid,noexec,nodev,ro")
 		root_mount("dev", "dev", "devtmpfs", "mode=0755,nosuid")
@@ -92,6 +94,8 @@ def init_mount(ctx: ArchBuilderContext):
 		root_mount("shm", "dev/shm", "tmpfs", "mode=1777,nosuid,nodev")
 		root_mount("run", "run", "tmpfs", "nosuid,nodev,mode=0755")
 		root_mount("tmp", "tmp", "tmpfs", "mode=1777,strictatime,nodev,nosuid")
+
+		# symbolic links for some script tools (e.g. mkinitcpio)
 		symlink("/proc/self/fd", "dev", "fd")
 		symlink("/proc/self/fd/0", "dev", "stdin")
 		symlink("/proc/self/fd/1", "dev", "stdout")

builder/build/names.py

@@ -7,6 +7,9 @@ log = getLogger(__name__)
 
 
 def gen_machine_info(ctx: ArchBuilderContext):
+	"""
+	Generate /etc/machine-info for systemd
+	"""
 	root = ctx.get_rootfs()
 	file = os.path.join(root, "etc/machine-info")
 	cfg = ctx.get("sysconf")
@@ -22,6 +25,9 @@ def gen_machine_info(ctx: ArchBuilderContext):
 
 
 def gen_hosts(ctx: ArchBuilderContext):
+	"""
+	Generate /etc/hosts
+	"""
 	addrs: list[str] = []
 	root = ctx.get_rootfs()
 	file = os.path.join(root, "etc/hosts")
@@ -33,6 +39,8 @@ def gen_hosts(ctx: ArchBuilderContext):
 			addrs.append(s[0])
 			f.write(addr)
 			f.write(os.linesep)
+
+		# 127.0.1.1 not set, add for FQDN
 		name = ctx.get("sysconf.hostname")
 		if "127.0.1.1" not in addrs and name:
 			f.write(f"127.0.1.1 {name}\n")
@@ -40,6 +48,9 @@ def gen_hosts(ctx: ArchBuilderContext):
 
 
 def gen_hostname(ctx: ArchBuilderContext):
+	"""
+	Generate /etc/hostname
+	"""
 	root = ctx.get_rootfs()
 	file = os.path.join(root, "etc/hostname")
 	name = ctx.get("sysconf.hostname")
@@ -51,6 +62,9 @@ def gen_hostname(ctx: ArchBuilderContext):
 
 
 def gen_environments(ctx: ArchBuilderContext):
+	"""
+	Generate /etc/environments
+	"""
 	root = ctx.get_rootfs()
 	file = os.path.join(root, "etc/environment")
 	envs: dict[str] = ctx.get("sysconf.environments", [])
@@ -62,6 +76,9 @@ def gen_environments(ctx: ArchBuilderContext):
 
 
 def proc_names(ctx: ArchBuilderContext):
+	"""
+	Apply names for system configs
+	"""
 	gen_machine_info(ctx)
 	gen_environments(ctx)
 	gen_hostname(ctx)

builder/build/pacman.py

@@ -7,6 +7,9 @@ log = getLogger(__name__)
 
 
 def install_all(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Install all pacman packages
+	"""
 	packages = ctx.get("pacman.install", [])
 	if len(packages) <= 0: return
 	log.info("installing packages: %s", " ".join(packages))
@@ -14,15 +17,24 @@ def install_all(ctx: ArchBuilderContext, pacman: Pacman):
 
 
 def install_all_keyring(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Install all pacman keyring packages before normal packages
+	"""
 	packages: list[str] = ctx.get("pacman.install", [])
 	if len(packages) <= 0: return
+
+	# find out all keyring packages
 	keyrings = [pkg for pkg in packages if pkg.endswith("-keyring")]
 	if len(keyrings) <= 0: return
+
 	log.info("installing keyrings: %s", " ".join(keyrings))
 	pacman.add_trust_keyring_pkg(keyrings)
 
 
 def uninstall_all(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Remove all specified pacman packages
+	"""
 	packages = ctx.get("pacman.uninstall", [])
 	if len(packages) <= 0: return
 	log.info("uninstalling packages: %s", " ".join(packages))
@@ -30,6 +42,9 @@ def uninstall_all(ctx: ArchBuilderContext, pacman: Pacman):
 
 
 def append_config(ctx: ArchBuilderContext, lines: list[str]):
+	"""
+	Generate basic pacman.conf for rootfs
+	"""
 	lines.append("[options]\n")
 	lines.append("HoldPkg = pacman glibc filesystem\n")
 	lines.append(f"Architecture = {ctx.tgt_arch}\n")
@@ -43,6 +58,9 @@ def append_config(ctx: ArchBuilderContext, lines: list[str]):
 
 
 def gen_config(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Generate full pacman.conf for rootfs
+	"""
 	conf = os.path.join(ctx.get_rootfs(), "etc/pacman.conf")
 	lines: list[str] = []
 	append_config(ctx, lines)
@@ -53,17 +71,30 @@ def gen_config(ctx: ArchBuilderContext, pacman: Pacman):
 
 
 def proc_pacman(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Install or remove packages for rootfs, and generate pacman.conf
+	"""
 	install_all(ctx, pacman)
 	uninstall_all(ctx, pacman)
 	gen_config(ctx, pacman)
 
 
 def proc_pacman_keyring(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Early install keyring packages
+	"""
 	install_all_keyring(ctx, pacman)
 
 
 def trust_all(ctx: ArchBuilderContext, pacman: Pacman):
+	"""
+	Early trust keyring for database and keyring packages
+	"""
 	if not ctx.gpgcheck: return
 	trust = ctx.get("pacman.trust", [])
+
+	# receive all keys now
 	pacman.recv_keys(trust)
+
+	# local sign keys
 	for key in trust: pacman.lsign_key(key)

builder/build/systemd.py

@@ -6,12 +6,19 @@ log = getLogger(__name__)
 
 
 def proc_systemd(ctx: ArchBuilderContext):
+	"""
+	Enable or disable systemd units files, and set default target
+	"""
 	systemd_comp.enable(ctx, ctx.get("systemd.enable", []))
 	systemd_comp.disable(ctx, ctx.get("systemd.disable", []))
 	systemd_comp.set_default(ctx, ctx.get("systemd.default", None))
 
 
 def proc_machine_id(ctx: ArchBuilderContext):
+	"""
+	Remove or set machine-id
+	Never duplicate machine id, it should generate when first boot
+	"""
 	id = ctx.get("machine-id", "")
 	root = ctx.get_rootfs()
 	mid = os.path.join(root, "etc/machine-id")

builder/build/user.py

@@ -6,61 +6,94 @@ log = getLogger(__name__)
 
 
 def proc_user(ctx: ArchBuilderContext, cfg: dict):
+	"""
+	Create a new user and set password
+	"""
 	if "name" not in cfg: raise ArchBuilderConfigError("username not set")
 	name = cfg["name"]
 	cmds = []
 	if ctx.passwd.lookup_name(name) is None:
+		# user is not exists, create it
 		cmds.append("useradd")
-		cmds.append("-m")
+		cmds.append("-m") # create home
 		action = "created"
 	else:
+		# user is already exists, modify it
 		cmds.append("usermod")
 		action = "modified"
+
+	# add all options
 	if "uid" in cfg: cmds.extend(["-u", str(cfg["uid"])])
 	if "gid" in cfg: cmds.extend(["-g", str(cfg["gid"])])
 	if "home" in cfg: cmds.extend(["-d", cfg["home"]])
 	if "shell" in cfg: cmds.extend(["-s", cfg["shell"]])
 	if "groups" in cfg: cmds.extend(["-G", str(cfg["groups"])])
 	cmds.append(name)
+
+	# run useradd or usermod
 	ret = chroot_run(ctx, cmds)
 	if ret != 0: raise OSError(f"{cmds[0]} failed")
+
+	# we want to set a password for user
 	if "password" in cfg:
 		cmds = ["chpasswd"]
 		text = f"{name}:{cfg['password']}\n"
 		ret = chroot_run(ctx, cmds, stdin=text)
 		if ret != 0: raise OSError("chpasswd failed")
+
+	# reload user database
 	ctx.reload_passwd()
 	log.info(f"{action} user {name}")
 
 
 def proc_group(ctx: ArchBuilderContext, cfg: dict):
+	"""
+	Create a new group
+	"""
 	if "name" not in cfg: raise ArchBuilderConfigError("groupname not set")
 	name = cfg["name"]
 	cmds = []
 	if ctx.passwd.lookup_name(name) is None:
+		# group is not exists, create it
 		cmds.append("groupadd")
 		action = "created"
 	else:
+		# group is already exists, modify it
 		cmds.append("groupmod")
 		action = "modified"
+
+	# add all options
 	if "gid" in cfg: cmds.extend(["-g", str(cfg["gid"])])
 	cmds.append(name)
+
+	# run groupadd or groupmod
 	ret = chroot_run(ctx, cmds)
 	if ret != 0: raise OSError(f"{name} failed")
+
+	# reload user database
 	ctx.reload_passwd()
 	log.info(f"{action} group {name}")
 
 
 def proc_users(ctx: ArchBuilderContext):
+	"""
+	Create all users
+	"""
 	for user in ctx.get("sysconf.user", []):
 		proc_user(ctx, user)
 
 
 def proc_groups(ctx: ArchBuilderContext):
+	"""
+	Create all groups
+	"""
 	for group in ctx.get("sysconf.group", []):
 		proc_group(ctx, group)
 
 
 def proc_usergroup(ctx: ArchBuilderContext):
-	proc_groups(ctx)
+	"""
+	Create all users and groups
+	"""
+	proc_groups(ctx) # create groups before users
 	proc_users(ctx)

builder/component/pacman.py

@@ -39,6 +39,9 @@ class Pacman:
 	caches: list[str]
 
 	def append_repos(self, lines: list[str]):
+		"""
+		Add all databases into config
+		"""
 		for repo in self.databases:
 			db = self.databases[repo]
 			lines.append(f"[{repo}]\n")
@@ -47,6 +50,9 @@ class Pacman:
 				lines.append(f"Server = {server}\n")
 
 	def append_config(self, lines: list[str]):
+		"""
+		Add basic pacman config for host
+		"""
 		siglevel = ("Required DatabaseOptional" if self.ctx.gpgcheck else "Never")
 		lines.append("[options]\n")
 		for cache in self.caches:
@@ -66,6 +72,9 @@ class Pacman:
 		self.append_repos(lines)
 
 	def init_keyring(self):
+		"""
+		Initialize pacman keyring
+		"""
 		path = os.path.join(self.ctx.work, "rootfs")
 		keyring = os.path.join(path, "etc/pacman.d/gnupg")
 		if not self.ctx.gpgcheck: return
@@ -76,6 +85,9 @@ class Pacman:
 		self.pacman_key(["--init"])
 
 	def init_config(self):
+		"""
+		Create host pacman.conf
+		"""
 		config = os.path.join(self.ctx.work, "pacman.conf")
 		if os.path.exists(config):
 			os.remove(config)
@@ -88,6 +100,9 @@ class Pacman:
 			f.writelines(lines)
 
 	def pacman_key(self, args: list[str]):
+		"""
+		Call pacman-key for rootfs
+		"""
 		if not self.ctx.gpgcheck:
 			raise RuntimeError("GPG check disabled")
 		keyring = os.path.join(self.root, "etc/pacman.d/gnupg")
@@ -100,6 +115,9 @@ class Pacman:
 		if ret != 0: raise OSError(f"pacman-key failed with {ret}")
 
 	def pacman(self, args: list[str]):
+		"""
+		Call pacman for rootfs
+		"""
 		config = os.path.join(self.ctx.work, "pacman.conf")
 		cmds = ["pacman"]
 		cmds.append("--noconfirm")
@@ -110,20 +128,32 @@ class Pacman:
 		if ret != 0: raise OSError(f"pacman failed with {ret}")
 
 	def add_database(self, repo: dict):
+		"""
+		Add a database and update it
+		"""
 		def resolve(url: str) -> str:
+			"""
+			Replace pacman.conf variables
+			"""
 			return (url
 				.replace("$arch", self.ctx.tgt_arch)
 				.replace("$repo", name))
 		if "name" not in repo:
 			raise ArchBuilderConfigError("repo name not set")
 		name = repo["name"]
+
+		# never add local into database
 		if name == "local" or "/" in name:
 			raise ArchBuilderConfigError("bad repo name")
+
+		# register database
 		if name not in self.databases:
 			self.databases[name] = self.handle.register_syncdb(
 				name, pyalpm.SIG_DATABASE_MARGINAL_OK
 			)
 		db = self.databases[name]
+
+		# add databases servers
 		servers: list[str] = []
 		if "server" in repo:
 			servers.append(resolve(repo["server"]))
@@ -131,10 +161,15 @@ class Pacman:
 			for server in repo["servers"]:
 				servers.append(resolve(server))
 		db.servers = servers
+
+		# update database now via pyalpm
 		log.info(f"updating database {name}")
 		db.update(False)
 
 	def load_databases(self):
+		"""
+		Add all databases and load them
+		"""
 		cfg = self.config
 		if "repo" not in cfg:
 			raise ArchBuilderConfigError("no repos found in config")
@@ -144,21 +179,33 @@ class Pacman:
 		self.refresh()
 
 	def lookup_package(self, name: str) -> list[pyalpm.Package]:
+		"""
+		Lookup pyalpm package by name
+		"""
+
+		# pass a filename, load it directly
 		if ".pkg.tar." in name:
 			pkg = self.handle.load_pkg(name)
 			if pkg is None: raise RuntimeError(f"load package {name} failed")
 			return [pkg]
+
 		s = name.split("/")
 		if len(s) == 2:
-			if s[0] not in self.databases:
+			# use DATABASE/PACKAGE, find it in database
+			if s[0] not in self.databases and s[0] != "local":
 				raise ValueError(f"database {s[0]} not found")
 			db = (self.handle.get_localdb() if s[0] == "local" else self.databases[s[0]])
 			pkg = db.get_pkg(s[1])
 			if pkg: return [pkg]
 			raise ValueError(f"package {s[1]} not found")
 		elif len(s) == 1:
+			# use PACKAGE, find it in all databases or find as group
+
+			# try find it as group
 			pkg = pyalpm.find_grp_pkgs(self.databases.values(), name)
 			if len(pkg) > 0: return pkg
+
+			# try find it as package
 			for dbn in self.databases:
 				db = self.databases[dbn]
 				pkg = db.get_pkg(name)
@@ -167,18 +214,27 @@ class Pacman:
 		raise ValueError(f"bad package name {name}")
 
 	def init_cache(self):
-		host_cache = "/var/cache/pacman/pkg"
-		work_cache = os.path.join(self.ctx.work, "packages")
-		root_cache = os.path.join(self.root, "var/cache/pacman/pkg")
+		"""
+		Initialize pacman cache folder
+		"""
+		host_cache = "/var/cache/pacman/pkg" # host cache
+		work_cache = os.path.join(self.ctx.work, "packages") # workspace cache
+		root_cache = os.path.join(self.root, "var/cache/pacman/pkg") # rootfs cache
 		self.caches.clear()
+
+		# host cache is existing, use host cache folder
 		if os.path.exists(host_cache):
 			self.caches.append(host_cache)
+
 		self.caches.append(work_cache)
 		self.caches.append(root_cache)
 		os.makedirs(work_cache, mode=0o0755, exist_ok=True)
 		os.makedirs(root_cache, mode=0o0755, exist_ok=True)
 
 	def __init__(self, ctx: ArchBuilderContext):
+		"""
+		Initialize pacman context
+		"""
 		self.ctx = ctx
 		if "pacman" not in ctx.config:
 			raise ArchBuilderConfigError("no pacman found in config")
@@ -200,6 +256,9 @@ class Pacman:
 		self.init_config()
 
 	def uninstall(self, pkgs: list[str]):
+		"""
+		Uninstall packages via pacman
+		"""
 		if len(pkgs) == 0: return
 		ps = " ".join(pkgs)
 		log.info(f"removing packages {ps}")
@@ -215,6 +274,9 @@ class Pacman:
 		asdeps: bool = False,
 		nodeps: bool = False,
 	):
+		"""
+		Install packages via pacman
+		"""
 		if len(pkgs) == 0: return
 		core_db = "var/lib/pacman/sync/core.db"
 		if not os.path.exists(os.path.join(self.root, core_db)):
@@ -229,6 +291,9 @@ class Pacman:
 		self.pacman(args)
 
 	def download(self, pkgs: list[str]):
+		"""
+		Download packages via pacman
+		"""
 		if len(pkgs) == 0: return
 		core_db = "var/lib/pacman/sync/core.db"
 		if not os.path.exists(os.path.join(self.root, core_db)):
@@ -239,6 +304,9 @@ class Pacman:
 		self.pacman(args)
 
 	def install_local(self, files: list[str]):
+		"""
+		Install a local packages via pacman
+		"""
 		if len(files) == 0: return
 		log.info("installing local packages %s", " ".join(files))
 		args = ["--needed", "--upgrade"]
@@ -246,12 +314,18 @@ class Pacman:
 		self.pacman(args)
 
 	def refresh(self, /, force: bool = False):
+		"""
+		Update local databases via pacman
+		"""
 		log.info("refresh pacman database")
 		args = ["--sync", "--refresh"]
 		if force: args.append("--refresh")
 		self.pacman(args)
 
 	def recv_keys(self, keys: str | list[str]):
+		"""
+		Receive a key via pacman-key
+		"""
 		args = ["--recv-keys"]
 		if type(keys) is str:
 			args.append(keys)
@@ -262,6 +336,9 @@ class Pacman:
 		self.pacman_key(args)
 
 	def lsign_key(self, key: str):
+		"""
+		Local sign a key via pacman-key
+		"""
 		self.pacman_key(["--lsign-key", key])
 
 	def pouplate_keys(
@@ -269,6 +346,9 @@ class Pacman:
 		names: str | list[str] = None,
 		folder: str = None
 	):
+		"""
+		Populate all keys via pacman-key
+		"""
 		args = ["--populate"]
 		if folder: args.extend(["--populate-from", folder])
 		if names is None: pass
@@ -278,31 +358,49 @@ class Pacman:
 		self.pacman_key(args)
 
 	def find_package_file(self, pkg: pyalpm.Package) -> str | None:
+		"""
+		Find out pacman package archive file in cache
+		"""
 		for cache in self.caches:
 			p = os.path.join(cache, pkg.filename)
 			if os.path.exists(p): return p
 		return None
 
 	def trust_keyring_pkg(self, pkg: pyalpm.Package):
+		"""
+		Trust a keyring package from file without install it
+		"""
 		if not self.ctx.gpgcheck: return
 		names: list[str] = []
 		target = os.path.join(self.ctx.work, "keyrings")
 		keyring = "usr/share/pacman/keyrings/"
+
+		# find out file path
 		path = self.find_package_file(pkg)
+
+		# cleanup keyring extract folder
 		if os.path.exists(target):
 			shutil.rmtree(target)
 		os.makedirs(target, mode=0o0755)
 		if path is None: raise RuntimeError(
 			f"package {pkg.name} not found"
 		)
+
+		# open keyring package to extract
 		log.debug(f"processing keyring package {pkg.name}")
 		with libarchive.file_reader(path) as archive:
 			for file in archive:
 				pn: str = file.pathname
 				if not pn.startswith(keyring): continue
+
+				# get the filename of file
 				fn = pn[len(keyring):]
 				if len(fn) <= 0: continue
+
+				# add keyring name to populate
 				if fn.endswith(".gpg"): names.append(fn[:-4])
+
+				# extract file
 				dest = os.path.join(target, fn)
 				log.debug(f"extracting {pn} to {dest}")
 				with open(dest, "wb") as f:
@@ -311,9 +409,14 @@ class Pacman:
 					fd = f.fileno()
 					os.fchmod(fd, file.mode)
 					os.fchown(fd, file.uid, file.gid)
+
+		# trust extracted keyring
 		self.pouplate_keys(names, target)
 
 	def add_trust_keyring_pkg(self, pkgnames: list[str]):
+		"""
+		Trust a keyring package from file without install it
+		"""
 		if not self.ctx.gpgcheck: return
 		if len(pkgnames) <= 0: return
 		self.download(pkgnames)

builder/component/systemd.py

@@ -4,13 +4,18 @@ from builder.lib.context import ArchBuilderContext
 
 
 def systemctl(ctx: ArchBuilderContext, args: list[str]):
+	"""
+	Call systemctl in rootfs
+	"""
 	path = ctx.get_rootfs()
 	full_args = ["systemctl"]
 	if utils.have_external("systemctl"):
+		# use host systemctl possible
 		full_args.append(f"--root={path}")
 		full_args.extend(args)
 		ret = ctx.run_external(full_args)
 	else:
+		# if host systemd is unavailable, use chroot run
 		full_args.extend(args)
 		ret = filesystem.chroot_run(ctx, full_args)
 	if ret != 0: raise OSError(
@@ -20,6 +25,9 @@ def systemctl(ctx: ArchBuilderContext, args: list[str]):
 
 
 def enable(ctx: ArchBuilderContext, units: list[str]):
+	"""
+	Enable systemd units
+	"""
 	if len(units) <= 0: return
 	args = ["enable", "--"]
 	args.extend(units)
@@ -27,6 +35,9 @@ def enable(ctx: ArchBuilderContext, units: list[str]):
 
 
 def disable(ctx: ArchBuilderContext, units: list[str]):
+	"""
+	Disable systemd units
+	"""
 	if len(units) <= 0: return
 	args = ["disable", "--"]
 	args.extend(units)
@@ -34,5 +45,8 @@ def disable(ctx: ArchBuilderContext, units: list[str]):
 
 
 def set_default(ctx: ArchBuilderContext, unit: str):
+	"""
+	Set default boot target for systemd
+	"""
 	if not unit: return
 	systemctl(ctx, ["set-default", "--", unit])

builder/component/user.py

@@ -62,9 +62,13 @@ def parse_user_from(
 	node: dict,
 	default: tuple[int, int] = (0, -1)
 ) -> tuple[int, int]:
-	if "owner" in node: return parse_owner(ctx, node["owner"])
-	uid = parse_usergroup_from(ctx, node, False, default[0])
-	gid = parse_usergroup_from(ctx, node, True, default[1])
+	"""
+	Parse user/group id from config
+	"""
+	uid, gid = default
+	if "owner" in node: uid, gid = parse_owner(ctx, node["owner"])
+	uid = parse_usergroup_from(ctx, node, False, uid)
+	gid = parse_usergroup_from(ctx, node, True, gid)
 	if gid == -1:
 		user = ctx.passwd.lookup_uid(uid)
 		if user is None: raise ArchBuilderConfigError(

builder/lib/area.py

@@ -23,10 +23,16 @@ class Area(SerializableDict):
 		}
 
 	def reset(self) -> Self:
+		"""
+		Remove all fields
+		"""
 		self.set(-1, -1, -1)
 		return self
 
 	def from_dict(self, o: dict) -> Self:
+		"""
+		Load all fields from config
+		"""
 		self.reset()
 		if "start" in o: self.start = size_to_bytes(o["start"])
 		if "offset" in o: self.start = size_to_bytes(o["offset"])
@@ -36,6 +42,9 @@ class Area(SerializableDict):
 		return self
 
 	def is_area_in(self, area: Self) -> bool:
+		"""
+		Is another area full in this area
+		"""
 		self.fixup()
 		area.fixup()
 		return (
@@ -45,6 +54,9 @@ class Area(SerializableDict):
 		)
 
 	def fixup(self) -> Self:
+		"""
+		Fill missing fields
+		"""
 		if self.start >= 0 and self.end >= 0 and self.start > self.end + 1:
 			raise ValueError("start large than end")
 		if 0 <= self.end < self.size and self.size >= 0:
@@ -52,17 +64,20 @@ class Area(SerializableDict):
 		if self.start >= 0 and self.end >= 0 and self.size >= 0:
 			if self.size != self.end - self.start + 1:
 				raise ValueError("bad size")
-		elif self.start >= 0 and self.end >= 0:
+		elif self.start >= 0 and self.end >= 0: # need size
 			self.size = self.end - self.start + 1
-		elif self.start >= 0 and self.size >= 0:
+		elif self.start >= 0 and self.size >= 0: # need end
 			self.end = self.start + self.size - 1
-		elif self.end >= 0 and self.size >= 0:
+		elif self.end >= 0 and self.size >= 0: # need start
 			self.start = self.end - self.size + 1
 		else:
 			raise ValueError("missing value")
 		return self
 
 	def __init__(self, start: int = -1, end: int = -1, size: int = -1, area: Self = None):
+		"""
+		Initialize a area
+		"""
 		super().__init__()
 		if area: start, end, size = area.to_tuple()
 		self.start, self.end, self.size = start, end, size
@@ -78,9 +93,15 @@ def to_tuple(start: int = -1, end: int = -1, size: int = -1, area: Area = None)
 
 class Areas(list[Area], SerializableList):
 	def is_area_in(self, area: Area) -> bool:
+		"""
+		Is an area fully in this areas
+		"""
 		return any(pool.is_area_in(area) for pool in self)
 
 	def merge(self) -> Self:
+		"""
+		Merge all areas
+		"""
 		idx = 0
 		self.sort(key=lambda x: (x.start, x.end))
 		while len(self) > 0:
@@ -91,6 +112,7 @@ class Areas(list[Area], SerializableList):
 			if idx > 0:
 				last = self[idx - 1]
 				if last.end + 1 >= curr.start:
+					# last end equals to this start
 					ent = Area(last.start, curr.end)
 					ent.fixup()
 					self.remove(last)
@@ -108,6 +130,9 @@ class Areas(list[Area], SerializableList):
 		size: int = -1,
 		area: Area = None,
 	) -> Area | None:
+		"""
+		Lookup an area with fields
+		"""
 		start, end, size = to_tuple(start, end, size, area)
 		for area in self:
 			if not (area.start <= start <= area.end): continue
@@ -117,6 +142,9 @@ class Areas(list[Area], SerializableList):
 		return None
 
 	def align(self, align: int) -> Self:
+		"""
+		Align all fields to value
+		"""
 		self.sort(key=lambda x: (x.start, x.end))
 		for area in self:
 			start = round_up(area.start, align)
@@ -136,6 +164,9 @@ class Areas(list[Area], SerializableList):
 		size: int = -1,
 		area: Area = None
 	) -> Area | None:
+		"""
+		Add an area to this areas
+		"""
 		if area: start, end, size = area.to_tuple()
 		cnt = (start >= 0) + (end >= 0) + (size >= 0)
 		if cnt < 2: raise ValueError("missing value")
@@ -151,6 +182,9 @@ class Areas(list[Area], SerializableList):
 		size: int = -1,
 		area: Area = None,
 	) -> bool:
+		"""
+		Remove a range from areas
+		"""
 		start, end, size = to_tuple(start, end, size, area)
 		if len(self) <= 0: return False
 		rs = min(area.start for area in self)
@@ -174,6 +208,9 @@ class Areas(list[Area], SerializableList):
 		area: Area = None,
 		biggest: bool = True,
 	) -> Area | None:
+		"""
+		Find matched area
+		"""
 		if area: start, end, size = area.to_tuple()
 		cnt = (start >= 0) + (end >= 0) + (size >= 0)
 		if cnt >= 2:

builder/lib/cgroup.py

@@ -11,27 +11,45 @@ class CGroup:
 
 	@property
 	def path(self) -> str:
+		"""
+		Get full path of this cgroup
+		"""
 		return os.path.join(self.fs, self.name)
 
 	@property
 	def valid(self) -> bool:
+		"""
+		Can read or write to this cgroup
+		"""
 		return os.path.exists(self.path)
 
 	def create(self):
+		"""
+		Create this cgroup now
+		"""
 		if self.valid: return
 		os.mkdir(self.path)
 
 	def destroy(self):
+		"""
+		Destroy the cgroup
+		"""
 		if not self.valid: return
 		os.rmdir(self.path)
 
 	def add_pid(self, pid: int):
+		"""
+		Add a pid to track
+		"""
 		if not self.valid: return
 		procs = os.path.join(self.path, "cgroup.procs")
 		with open(procs, "w") as f:
 			f.write(f"{pid}\n")
 
 	def list_pid(self) -> list[int]:
+		"""
+		List all tracked children progress id
+		"""
 		ret: list[int] = []
 		if not self.valid: return ret
 		procs = os.path.join(self.path, "cgroup.procs")
@@ -41,22 +59,36 @@ class CGroup:
 		return ret
 
 	def kill_all(self, sig: int = signal.SIGTERM, timeout: int = 10, kill: int = 8):
+		"""
+		Kill all children process and wait them exit
+		"""
 		if not self.valid: return
 		pids = self.list_pid()
 		remain = 0
 		while True:
+			# send a signal
 			for pid in pids:
 				log.debug(f"killing {pid}")
 				try: os.kill(pid, sig)
 				except: pass
+
+			# waitpid to clean zombie
 			try: os.waitpid(-1, os.WNOHANG)
 			except: pass
+
+			# check all children was exited
 			pids = self.list_pid()
 			if len(pids) <= 0: break
+
+			# set to SIGKILL when reached kill time
 			if 0 < kill <= remain:
 				sig = signal.SIGKILL
+
+			# timeoutd, throw out
 			if remain >= timeout:
 				raise TimeoutError("killing pids timedout")
+
+			# wait...
 			time.sleep(1)
 
 	def __init__(self, name: str, fs: str = None):

builder/lib/config.py

@@ -12,6 +12,9 @@ class ArchBuilderConfigError(Exception):
 
 
 def _dict_merge(dst: dict, src: dict):
+	"""
+	Merge two dict with override
+	"""
 	for key in src.keys():
 		st = type(src[key])
 		if key in dst and st is type(dst[key]):

builder/lib/context.py

@@ -89,6 +89,9 @@ class ArchBuilderContext:
 	group: GroupFile = GroupFile()
 
 	def get(self, key: str, default=None):
+		"""
+		Get config value
+		"""
 		try: return dict_get(key, self.config)
 		except: return default
 
@@ -104,6 +107,9 @@ class ArchBuilderContext:
 		self.cleanup()
 
 	def cleanup(self):
+		"""
+		Cleanup build context
+		"""
 		from builder.build.mount import undo_mounts
 		self.cgroup.kill_all()
 		self.cgroup.destroy()
@@ -139,6 +145,9 @@ class ArchBuilderContext:
 		return ret
 
 	def reload_passwd(self):
+		"""
+		Reload user database
+		"""
 		root = self.get_rootfs()
 		pf = os.path.join(root, "etc/passwd")
 		gf = os.path.join(root, "etc/group")
@@ -148,9 +157,15 @@ class ArchBuilderContext:
 		if os.path.exists(gf): self.group.load_file(gf)
 
 	def finish_config(self):
+		"""
+		Done load configs
+		"""
 		self.config_orig = deepcopy(self.config)
 
 	def resolve_subscript(self):
+		"""
+		Run subscript replaces
+		"""
 		ss = SubScript()
 		self.config = deepcopy(self.config_orig)
 		ss.parse(self.config)

builder/lib/json.py

@@ -4,6 +4,9 @@ from builder.lib import serializable
 
 
 class SerializableEncoder(json.JSONEncoder):
+	"""
+	JSON implement of serializable interface
+	"""
 	def default(self, o):
 		if isinstance(o, UUID):
 			return str(o)

builder/lib/mount.py

@@ -33,6 +33,9 @@ class MountPoint(SerializableDict):
 
 	@property
 	def virtual(self) -> bool:
+		"""
+		Is current mount point a virtual filesystem
+		"""
 		if self.fstype:
 			if self.fstype in virtual_fs: return True
 			if self.fstype in real_fs: return False
@@ -45,6 +48,12 @@ class MountPoint(SerializableDict):
 
 	@property
 	def level(self) -> int:
+		"""
+		Get current target levels
+		/ => 1
+		/boot => 2
+		/usr/bin => 3
+		"""
 		if self.target is None: return 0
 		path = os.path.realpath(self.target)
 		cnt = path.count(os.sep)
@@ -56,13 +65,22 @@ class MountPoint(SerializableDict):
 
 	@property
 	def options(self):
+		"""
+		Get options as string
+		"""
 		return ",".join(self.option)
 
 	@options.setter
 	def options(self, val: str):
+		"""
+		Set options from string
+		"""
 		self.option = val.split(",")
 
 	def get_option(self, opt: str) -> str | None:
+		"""
+		Get an option from string
+		"""
 		if opt in self.option:
 			return opt
 		if "=" not in opt:
@@ -72,6 +90,9 @@ class MountPoint(SerializableDict):
 		return None
 
 	def remove_option(self, opt: str | list[str]) -> Self:
+		"""
+		Remove an option
+		"""
 		if type(opt) is list[str]:
 			for o in opt:
 				self.remove_option(o)
@@ -86,11 +107,17 @@ class MountPoint(SerializableDict):
 		return self
 
 	def exclusive_option(self, opt: str, opt1: str, opt2: str) -> Self:
+		"""
+		Remove a exclusive option
+		"""
 		if opt == opt1 or opt == opt2:
 			self.remove_option(opt1)
 		return self
 
 	def add_option(self, opt: str) -> Self:
+		"""
+		Add an option
+		"""
 		self.exclusive_option(opt, "ro", "rw")
 		self.exclusive_option(opt, "dev", "nodev")
 		self.exclusive_option(opt, "suid", "nosuid")
@@ -102,10 +129,16 @@ class MountPoint(SerializableDict):
 		return self
 
 	def ro(self) -> Self:
+		"""
+		Set mount point to read-only
+		"""
 		self.add_option("ro")
 		return self
 
 	def rw(self) -> Self:
+		"""
+		Set mount point to read-write
+		"""
 		self.add_option("rw")
 		return self
 
@@ -115,6 +148,9 @@ class MountPoint(SerializableDict):
 	def have_options(self) -> bool: return len(self.option) > 0
 
 	def update_device(self):
+		"""
+		Update device field from source
+		"""
 		if self.virtual or self.source is None: return
 		if self.source.startswith(os.sep):
 			self.device = self.source
@@ -124,6 +160,9 @@ class MountPoint(SerializableDict):
 			return
 
 	def persist_source(self, tag: str = "UUID"):
+		"""
+		Change source to persist source
+		"""
 		if self.virtual: return
 		if self.device is None: self.update_device()
 		if self.device is None: return
@@ -136,6 +175,9 @@ class MountPoint(SerializableDict):
 		)
 
 	def tolibmount(self) -> libmount.Context:
+		"""
+		To util-linux libmount context
+		"""
 		mnt = libmount.Context()
 		mnt.target = self.target
 		if self.have_source(): mnt.source = self.source
@@ -144,9 +186,15 @@ class MountPoint(SerializableDict):
 		return mnt
 
 	def ismount(self) -> bool:
+		"""
+		Is current mount point mounted
+		"""
 		return os.path.ismount(self.target)
 
 	def mount(self) -> Self:
+		"""
+		Mount now
+		"""
 		if not os.path.exists(self.target):
 			os.makedirs(self.target, mode=0o0755)
 		if not os.path.ismount(self.target):
@@ -161,6 +209,9 @@ class MountPoint(SerializableDict):
 		return self
 
 	def umount(self) -> Self:
+		"""
+		UnMount now
+		"""
 		if os.path.ismount(self.target):
 			lib = self.tolibmount()
 			lib.umount()
@@ -168,6 +219,9 @@ class MountPoint(SerializableDict):
 		return self
 
 	def from_mount_line(self, line: str) -> Self:
+		"""
+		Load from mtab / fstab
+		"""
 		d = line.split()
 		if len(d) != 6:
 			raise ValueError("bad mount line")
@@ -180,6 +234,10 @@ class MountPoint(SerializableDict):
 		return self
 
 	def to_mount_line(self) -> str:
+		"""
+		To mount tab line string
+		PARTLABEL=
+		"""
 		self.fixup()
 		fields = [
 			self.source,
@@ -246,6 +304,9 @@ class MountPoint(SerializableDict):
 
 class MountTab(list[MountPoint], SerializableList):
 	def find_folder(self, folder: str) -> Self:
+		"""
+		Find mount point target starts with folder
+		"""
 		root = os.path.realpath(folder)
 		return [mnt for mnt in self if mnt.target.startswith(root)]
 
@@ -254,12 +315,18 @@ class MountTab(list[MountPoint], SerializableList):
 	def find_fstype(self, fstype: str) -> Self: return [mnt for mnt in self if mnt.fstype == fstype]
 
 	def clone(self) -> Self:
+		"""
+		Fully clone a MountTab
+		"""
 		mnts = MountTab()
 		for mnt in self:
 			mnts.append(mnt.clone())
 		return mnts
 
 	def mount_all(self, prefix: str = None, mkdir: bool = False) -> Self:
+		"""
+		Mount all mount points
+		"""
 		for mnt in self:
 			m = mnt.clone()
 			if prefix:
@@ -271,9 +338,15 @@ class MountTab(list[MountPoint], SerializableList):
 		return self
 
 	def resort(self):
+		"""
+		Sort mount points by path level
+		"""
 		self.sort(key=lambda x: (x.level, len(x.target), x.target))
 
 	def strip_virtual(self) -> Self:
+		"""
+		Remove all virtual filesystem mount points
+		"""
 		for mnt in self:
 			if mnt.virtual:
 				self.remove(mnt)
@@ -288,6 +361,9 @@ class MountTab(list[MountPoint], SerializableList):
 		return self
 
 	def to_mount_file(self, linesep=os.linesep) -> str:
+		"""
+		Convert to mount file (fstab)
+		"""
 		ret = "# Source Target FS-Type Options FS-Freq FS-Dump"
 		ret += linesep
 		for point in self:

builder/lib/shadow.py

@@ -4,10 +4,16 @@ from builder.lib.serializable import SerializableDict, SerializableList
 
 
 def zero2empty(num: int) -> str:
+	"""
+	Convert number to string, when zero return empty
+	"""
 	return str(num) if num != 0 else ""
 
 
 def none2empty(val: str) -> str:
+	"""
+	Return a string, when None return empty
+	"""
 	return val if val else ""
 
 
@@ -25,6 +31,9 @@ class UserFile(SerializableList):
 	def unload(self): pass
 
 	def load_str(self, content: str | list[str]) -> Self:
+		"""
+		Load whole file as string
+		"""
 		if type(content) is str: 
 			content = content.split("\n")
 		for line in content:

builder/lib/utils.py

@@ -13,6 +13,9 @@ def str_find_all(
 	start: typing.SupportsIndex | None = None,
 	end: typing.SupportsIndex | None = None,
 ) -> int:
+	"""
+	Find the closest string with multiple key
+	"""
 	if type(keys) is str: return orig.find(keys, start, end)
 	result: list[int] = [orig.find(key, start, end) for key in keys]
 	while -1 in result: result.remove(-1)
@@ -20,6 +23,11 @@ def str_find_all(
 
 
 def parse_cmd_args(cmd: str | list[str]) -> list[str]:
+	"""
+	Parse command line to list
+	parse_cmd_args("ls -la /mnt") = ["ls", "-la", "/mnt"]
+	parse_cmd_args(["ls", "-la", "/mnt"]) = ["ls", "-la", "/mnt"]
+	"""
 	if type(cmd) is str: return shlex.split(cmd)
 	elif type(cmd) is list: return cmd
 	else: raise TypeError("unknown type for cmd")
@@ -49,16 +57,37 @@ def fd_get_path(fd: int) -> str | None:
 	fd_get_path(1) = "/dev/pts/0"
 	"""
 	link = f"/proc/self/fd/{fd}"
+
+	# target is not exists?
 	if not os.path.exists(link): return None
+
+	# read link of fd
 	path = os.readlink(link)
+
+	# must starts with / (is an absolute path)
 	if not path.startswith("/"): return None
+
+	# do not use memfd
 	if path.startswith("/memfd:"): return None
+
+	# do not use a deleted file
 	if path.endswith(" (deleted)"): return None
+
+	# target file is not exists (should not happen)
 	if not os.path.exists(path): return None
+
 	return path
 
 
 def size_to_bytes(value: str | int, alt_units: dict = None) -> int:
+	"""
+	Convert human-readable size string to number
+	size_to_bytes("1MiB") = 1048576
+	size_to_bytes("4K") = 4096
+	size_to_bytes("64b") = 8
+	size_to_bytes(123) = 123
+	size_to_bytes("2048s", {'s': 512}) = 1048576
+	"""
 	units = {
 		'b': 0.125, 'bit': 0.125, 'bits': 0.125, 'Bit': 0.125, 'Bits': 0.125,
 		'B': 1, 'Byte': 1, 'Bytes': 1, 'bytes': 1, 'byte': 1,
@@ -71,45 +100,89 @@ def size_to_bytes(value: str | int, alt_units: dict = None) -> int:
 		'z': 10**15, 'zB': 10**15, 'zb': 10**15, 'Z': 2**50, 'ZB': 2**50, 'ZiB': 2**50,
 		'y': 10**15, 'yB': 10**15, 'yb': 10**15, 'Y': 2**50, 'YB': 2**50, 'YiB': 2**50,
 	}
-	if type(value) is int: return value
+	if type(value) is int:
+		# return number directly
+		return value
 	elif type(value) is str:
+		# add custom units
 		if alt_units: units.update(alt_units)
+
+		# find all matched units
 		matches = {unit: len(unit) for unit in units if value.endswith(unit)}
+
+		# find out the longest matched unit
 		max_unit = max(matches.values(), default=0)
+
+		# use the longest unit
 		unit = next((unit for unit in matches.keys() if matches[unit] == max_unit), None)
+
+		# get mul for target unit
 		mul = units[unit] if unit else 1.0
+
+		# convert string to target number
 		return int(float(value[:len(value)-max_unit].strip()) * mul)
 	else: raise TypeError("bad size value")
 
 
 def bytes_pad(b: bytes, size: int, trunc: bool = False, pad: bytes = b'\0') -> bytes:
+	"""
+	Padding a bytes to specified length
+	"""
 	l = len(b)
-	if l > size and trunc: b = b[:size]
-	if l < size: b += pad * (size - l)
+
+	# if larger than specified size, truncate
+	if l > size and trunc:
+		b = b[:size]
+
+	# if smaller than specified size, padding
+	if l < size:
+		b += pad * (size - l)
 	return b
 
 
 def round_up(value: int, align: int) -> int:
+	"""
+	Align up a number
+	round_down(0x2000, 0x1000) = 0x2000
+	round_down(0x2001, 0x1000) = 0x3000
+	round_down(0x1FFF, 0x1000) = 0x2000
+	"""
 	return (value + align - 1) & ~(align - 1)
 
 
 def round_down(value: int, align: int) -> int:
+	"""
+	Align down a number
+	round_down(0x2000, 0x1000) = 0x2000
+	round_down(0x2001, 0x1000) = 0x2000
+	round_down(0x1FFF, 0x1000) = 0x1000
+	"""
 	return value & ~(align - 1)
 
 
 def open_config(path: str, mode=0o0644) -> io.TextIOWrapper:
+	"""
+	Open a config file for write
+	If original file is existing, move to FILE.dist
+	"""
 	dist = f"{path}.dist"
 	have_dist = False
 	if os.path.exists(dist):
+		# dist file already exists, no move
 		have_dist = True
 	elif os.path.exists(path):
+		# target file already exists, rename to dist
 		shutil.move(path, dist)
 		have_dist = True
+	# FIXME: should not move previous write to dist
+
+	# open and truncate
 	flags = os.O_RDWR | os.O_CREAT | os.O_TRUNC
 	fd = os.open(path=path, flags=flags, mode=mode)
 	if fd < 0: raise IOError(f"open {path} failed")
 	try:
 		fp = os.fdopen(fd, "w")
+		# write a comment to tell user dist was renamed
 		fp.write("# This file is auto generated by arch-image-builder\n")
 		if have_dist:
 			fn = os.path.basename(dist)
@@ -119,10 +192,18 @@ def open_config(path: str, mode=0o0644) -> io.TextIOWrapper:
 	except:
 		os.close(fd)
 		raise
+	# file close managed by parent function
 	return fp
 
 
 def path_to_name(path: str) -> str:
+	"""
+	Convert path to a identifier
+	path_to_name("") = "empty"
+	path_to_name("/") = "rootfs"
+	path_to_name("/boot") = "boot"
+	path_to_name("/etc/fstab") = "etc-fstab"
+	"""
 	if path == "/": return "rootfs"
 	if path.startswith("/"): path = path[1:]
 	if len(path) <= 0: return "empty"

configs/common/alarm-user.yaml

@@ -1,3 +1,4 @@
+# Default user for ArchLinux ARM
 sysconf:
   user:
   - name: alarm

configs/common/arch-user.yaml

@@ -1,3 +1,4 @@
+# Default user for ArchLinux
 sysconf:
   user:
   - name: arch

configs/common/wheel-nopasswd.yaml

@@ -1,5 +1,7 @@
+# Users in wheel group can run root commands without password
 filesystem:
   files:
+  # polkit
   - path: /etc/polkit-1/rules.d/99-wheel.rules
     mode: 0640
     content: |
@@ -7,10 +9,12 @@ filesystem:
         if(subject.isInGroup("wheel"))
           return polkit.Result.YES;
       });
+  # sudo
   - path: /etc/sudoers.d/wheel
     mode: 0640
     content: |
       %wheel ALL=(ALL:ALL) NOPASSWD: ALL
+# Ensure sudo is installed
 pacman:
   install:
   - sudo

configs/desktop/gnome.yaml

@@ -1,3 +1,4 @@
+# GNOME desktop
 pacman:
   install:
   - gnome
@@ -6,4 +7,5 @@ systemd:
   enable:
   - gdm.service
 +also:
+# Ensure NetworkManager is enabled
 - packages/network-manager

configs/device/ayn-odin2.yaml

@@ -2,20 +2,36 @@ name: AYN Odin 2
 arch: aarch64
 soc: qcs8550
 device: ayn-odin2
+
+# hypdtbo for platform ABL boot
 device_suffix: -hypdtbo
 pacman:
   install:
+
+  # For regulatory.db
   - wireless-regdb
+
+  # Qualcomm firmwares for AYN Odin2
   - linux-firmware-ayn-odin2
+
+  # Mainline kernel for AYN Odin2
   - linux-ayn-odin2-edge
+
+  # Adreno 740 GPU
   - mesa-qcom-git
+
+  # Vulkan test tools
   - vulkan-tools
+
+  # Vulkan dependency
   - xcb-util-keysyms
 systemd:
   disable:
+  # No modem in this device
   - rmtfs.service
 filesystem:
   files:
+  # GamePAD workaround
   - path: /etc/udev/rules.d/99-${device}.rules
     content: |
       SUBSYSTEM=="input", ATTRS{name}=="Ayn Odin2 Gamepad", MODE="0666", ENV{ID_INPUT_MOUSE}="0", ENV{ID_INPUT_JOYSTICK}="1"
@@ -41,6 +57,7 @@ filesystem:
 sysconf:
   chassis: handset
   environments:
+    # Force to use zink driver for OpenGL
     __GLX_VENDOR_LIBRARY_NAME: mesa
     MESA_LOADER_DRIVER_OVERRIDE: zink
     GALLIUM_DRIVER: zink
@@ -53,6 +70,8 @@ kernel:
   - allow_mismatched_32bit_el0
 mkinitcpio:
   files:
+  # Put these firmware to initramfs for boot
+  # TODO: do not put they into initramfs
   - /usr/lib/firmware/qcom/sm8550/ayn/odin2/adsp.mbn
   - /usr/lib/firmware/qcom/sm8550/ayn/odin2/adsp_dtb.mbn
   - /usr/lib/firmware/qcom/sm8550/ayn/odin2/cdsp.mbn
@@ -72,8 +91,18 @@ mkinitcpio:
 - os/archlinuxarm
 - repo/archlinuxcn
 - repo/renegade-project
+
+# Generic qualcomm related config
 - device/qcom
+
+# USB Gadget tools
 - packages/systemd-gadget
+
+# OpenSSH Server
 - packages/openssh
+
+# Text editor
 - packages/editor
+
+# Bluetooth related services
 - packages/bluez

configs/device/qcom.yaml

@@ -2,10 +2,19 @@ platform: qcom
 device_suffix:
 pacman:
   install:
+  # Android A/B Slot Switcher
   - qbootctl
+
+  # Qualcomm IPC Router
   - qrtr
+
+  # Modem remote filesystem
   - rmtfs
+
+  # TFTP via Qualcomm IPC Router
   - tqftpserv
+
+  # Protection Domain Mapper
   - pd-mapper
 systemd:
   enable:

configs/locale/zh-cn.yaml

@@ -1,31 +1,44 @@
+# I18N for Chinese (Simplified)
 locale:
   enable:
   - "zh_CN.UTF-8 UTF-8"
   - "en_US.UTF-8 UTF-8"
   default: zh_CN.UTF-8
+
 filesystem:
   files:
+
+  # Wireless regulatory
   - path: /etc/conf.d/wireless-regdom
     content: |
       WIRELESS_REGDOM="CN"
+
+  # China accelerated DNS
   - path: /etc/systemd/resolved.conf.d/cn-dns.conf
     content: |
       [Resolve]
       DNS=114.114.114.114 119.29.29.29
       FallbackDNS=114.114.114.114 119.29.29.29
+
+  # China accelerated NTP Server
   - path: /etc/systemd/timesyncd.conf.d/cn-ntp.conf
     content: |
       [Time]
       NTP=cn.ntp.org.cn
+
 pacman:
   install:
+  # Fonts for CJK language
   - noto-fonts-cjk
   - wqy-bitmapfont
   - wqy-microhei
   - wqy-microhei-lite
   - wqy-zenhei
+
+  # Input method for Chinese
   - ibus
   - ibus-libpinyin
+
 sysconf:
   environments:
     GTK_IM_MODULE: ibus

configs/packages/bluez.yaml

@@ -1,3 +1,4 @@
+# Bluetooth
 pacman:
   install:
   - bluez

configs/packages/systemd-gadget.yaml

@@ -1,10 +1,13 @@
+# USB Gadget tools
 pacman:
   install:
   - systemd-gadget
   - dnsmasq
 systemd:
   disable:
+  # Disable tty ACM to avoid bugs
   - getty@ttyGS0.service
   - usbgadget-func-acm.service
   enable:
+  # Enable systemd-networkd for RNDIS
   - systemd-networkd.service

configs/packages/systemd-networkd.yaml

@@ -1,5 +1,6 @@
 filesystem:
   files:
+    # Network configs from archiso
     - path: /etc/systemd/network/20-ethernet.network
       content: |
         [Match]