120 lines
3.8 KiB
Python
120 lines
3.8 KiB
Python
"""
|
|
Copyright 2020 Oliver Smith
|
|
|
|
This file is part of pmbootstrap.
|
|
|
|
pmbootstrap is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
pmbootstrap is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with pmbootstrap. If not, see <http://www.gnu.org/licenses/>.
|
|
"""
|
|
import os
|
|
import pmb.helpers.run
|
|
|
|
|
|
def ismount(folder):
|
|
"""
|
|
Ismount() implementation, that works for mount --bind.
|
|
Workaround for: https://bugs.python.org/issue29707
|
|
"""
|
|
folder = os.path.realpath(os.path.realpath(folder))
|
|
with open("/proc/mounts", "r") as handle:
|
|
for line in handle:
|
|
words = line.split()
|
|
if len(words) >= 2 and words[1] == folder:
|
|
return True
|
|
if words[0] == folder:
|
|
return True
|
|
return False
|
|
|
|
|
|
def bind(args, source, destination, create_folders=True, umount=False):
|
|
"""
|
|
Mount --bind a folder and create necessary directory structure.
|
|
:param umount: when destination is already a mount point, umount it first.
|
|
"""
|
|
# Check/umount destination
|
|
if ismount(destination):
|
|
if umount:
|
|
umount_all(args, destination)
|
|
else:
|
|
return
|
|
|
|
# Check/create folders
|
|
for path in [source, destination]:
|
|
if os.path.exists(path):
|
|
continue
|
|
if create_folders:
|
|
pmb.helpers.run.root(args, ["mkdir", "-p", path])
|
|
else:
|
|
raise RuntimeError("Mount failed, folder does not exist: " +
|
|
path)
|
|
|
|
# Actually mount the folder
|
|
pmb.helpers.run.root(args, ["mount", "--bind", source, destination])
|
|
|
|
# Verify, that it has worked
|
|
if not ismount(destination):
|
|
raise RuntimeError("Mount failed: " + source + " -> " + destination)
|
|
|
|
|
|
def bind_blockdevice(args, source, destination):
|
|
"""
|
|
Mount a blockdevice with the --bind option, and create the destination
|
|
file, if necessary.
|
|
"""
|
|
# Skip existing mountpoint
|
|
if ismount(destination):
|
|
return
|
|
|
|
# Create empty file
|
|
if not os.path.exists(destination):
|
|
pmb.helpers.run.root(args, ["touch", destination])
|
|
|
|
# Mount
|
|
pmb.helpers.run.root(args, ["mount", "--bind", source,
|
|
destination])
|
|
|
|
|
|
def umount_all_list(prefix, source="/proc/mounts"):
|
|
"""
|
|
Parses `/proc/mounts` for all folders beginning with a prefix.
|
|
:source: can be changed for testcases
|
|
:returns: a list of folders, that need to be umounted
|
|
"""
|
|
ret = []
|
|
prefix = os.path.realpath(prefix)
|
|
with open(source, "r") as handle:
|
|
for line in handle:
|
|
words = line.split()
|
|
if len(words) < 2:
|
|
raise RuntimeError("Failed to parse line in " + source + ": " +
|
|
line)
|
|
mountpoint = words[1]
|
|
if mountpoint.startswith(prefix):
|
|
# Remove "\040(deleted)" suffix (#545)
|
|
deleted_str = r"\040(deleted)"
|
|
if mountpoint.endswith(deleted_str):
|
|
mountpoint = mountpoint[:-len(deleted_str)]
|
|
ret.append(mountpoint)
|
|
ret.sort(reverse=True)
|
|
return ret
|
|
|
|
|
|
def umount_all(args, folder):
|
|
"""
|
|
Umount all folders, that are mounted inside a given folder.
|
|
"""
|
|
for mountpoint in umount_all_list(folder):
|
|
pmb.helpers.run.root(args, ["umount", mountpoint])
|
|
if ismount(mountpoint):
|
|
raise RuntimeError("Failed to umount: " + mountpoint)
|