arch-image-builder/builder/build/fstab.py
BigfootACA 067ee2d341 add more comments
Signed-off-by: BigfootACA <bigfoot@classfun.cn>
2024-05-20 09:56:42 +08:00

86 lines
2.2 KiB
Python

import os
from logging import getLogger
from builder.lib.context import ArchBuilderContext
from builder.lib.utils import open_config
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 == "/":
# 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":
# 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)
def proc_fstab(ctx: ArchBuilderContext):
ctx.fstab.resort()
write_fstab(ctx)
mount_all(ctx)