Add submount directory to PartitionMount class

This allows the partition to be mounted on a directory underneath the
temporary directory, eg. /rootfs/, to help support creating other image
types without needed to move the files around.
This commit is contained in:
Brian C. Lane 2015-10-19 15:33:30 -07:00
parent 0b8b74edda
commit b96fd98af3

View File

@ -27,6 +27,7 @@ import sys
import traceback import traceback
import multiprocessing import multiprocessing
from time import sleep from time import sleep
import shutil
from pylorax.sysutils import cpfile from pylorax.sysutils import cpfile
from pylorax.executils import execWithRedirect, execWithCapture from pylorax.executils import execWithRedirect, execWithCapture
@ -305,17 +306,30 @@ class Mount(object):
class PartitionMount(object): class PartitionMount(object):
""" Mount a partitioned image file using kpartx """ """ Mount a partitioned image file using kpartx """
def __init__(self, disk_img, mount_ok=None): def __init__(self, disk_img, mount_ok=None, submount=None):
""" """
disk_img is the full path to a partitioned disk image :param str disk_img: The full path to a partitioned disk image
mount_ok is a function that is passed the mount point and :param mount_ok: A function that is passed the mount point and
returns True if it should be mounted. returns True if it should be mounted.
:param str submount: Directory inside mount_dir to mount at
If mount_ok is not set it will look for /etc/passwd
If the partition is found it will be mounted under a temporary
directory and self.temp_dir set to it. If submount is passed it will be
created and mounted there instead, with self.mount_dir set to point to
it. self.mount_dev is set to the loop device, and self.mount_size is
set to the size of the partition.
When no subdir is passed self.temp_dir and self.mount_dir will be the same.
""" """
self.mount_dev = None self.mount_dev = None
self.mount_size = None self.mount_size = None
self.mount_dir = None self.mount_dir = None
self.disk_img = disk_img self.disk_img = disk_img
self.mount_ok = mount_ok self.mount_ok = mount_ok
self.submount = submount
self.temp_dir = None
# Default is to mount partition with /etc/passwd # Default is to mount partition with /etc/passwd
if not self.mount_ok: if not self.mount_ok:
@ -339,7 +353,12 @@ class PartitionMount(object):
def __enter__(self): def __enter__(self):
# Mount the device selected by mount_ok, if possible # Mount the device selected by mount_ok, if possible
mount_dir = tempfile.mkdtemp() self.temp_dir = tempfile.mkdtemp()
if self.submount:
mount_dir = os.path.normpath(os.path.sep.join([self.temp_dir, self.submount]))
os.makedirs(mount_dir, mode=0o755, exist_ok=True)
else:
mount_dir = self.temp_dir
for dev, size in self.loop_devices: for dev, size in self.loop_devices:
try: try:
mount( "/dev/mapper/"+dev, mnt=mount_dir ) mount( "/dev/mapper/"+dev, mnt=mount_dir )
@ -355,14 +374,16 @@ class PartitionMount(object):
logger.info("Partition mounted on %s size=%s", self.mount_dir, self.mount_size) logger.info("Partition mounted on %s size=%s", self.mount_dir, self.mount_size)
else: else:
logger.debug("Unable to mount anything from %s", self.disk_img) logger.debug("Unable to mount anything from %s", self.disk_img)
os.rmdir(mount_dir) os.rmdir(self.temp_dir)
self.temp_dir = None
return self return self
def __exit__(self, exc_type, exc_value, tracebk): def __exit__(self, exc_type, exc_value, tracebk):
if self.mount_dir: if self.temp_dir:
umount(self.mount_dir) umount(self.mount_dir)
os.rmdir(self.mount_dir) shutil.rmtree(self.temp_dir)
self.mount_dir = None self.mount_dir = None
self.temp_dir = None
execWithRedirect("kpartx", ["-d", "-s", self.disk_img]) execWithRedirect("kpartx", ["-d", "-s", self.disk_img])