mirror of
https://gitlab.com/libvirt/libvirt-python.git
synced 2025-07-07 16:59:38 +03:00
74a78fa42c
indent by 4 spaces one spaces around assignments Signed-off-by: Philipp Hahn <hahn@univention.de>
130 lines
3.8 KiB
Python
Executable File
130 lines
3.8 KiB
Python
Executable File
#!/usr/bin/env python3
|
|
"""
|
|
Either uploads local FILE to libvirt VOLUME, or downloads libvirt
|
|
VOLUME into local FILE while preserving FILE/VOLUME sparseness
|
|
"""
|
|
# Example of sparse streams usage
|
|
#
|
|
# Authors:
|
|
# Michal Privoznik <mprivozn@redhat.com>
|
|
|
|
import libvirt
|
|
import os
|
|
from argparse import ArgumentParser
|
|
|
|
|
|
def bytesWriteHandler(stream: libvirt.virStream, buf: bytes, opaque: int) -> int:
|
|
fd = opaque
|
|
return os.write(fd, buf)
|
|
|
|
|
|
def bytesReadHandler(stream: libvirt.virStream, nbytes: int, opaque: int) -> bytes:
|
|
fd = opaque
|
|
return os.read(fd, nbytes)
|
|
|
|
|
|
def recvSkipHandler(stream: libvirt.virStream, length: int, opaque: int) -> None:
|
|
fd = opaque
|
|
cur = os.lseek(fd, length, os.SEEK_CUR)
|
|
return os.ftruncate(fd, cur)
|
|
|
|
|
|
def sendSkipHandler(stream: libvirt.virStream, length: int, opaque: int) -> int:
|
|
fd = opaque
|
|
return os.lseek(fd, length, os.SEEK_CUR)
|
|
|
|
|
|
def holeHandler(stream: libvirt.virStream, opaque: int):
|
|
fd = opaque
|
|
cur = os.lseek(fd, 0, os.SEEK_CUR)
|
|
|
|
try:
|
|
data = os.lseek(fd, cur, os.SEEK_DATA)
|
|
except OSError as e:
|
|
if e.errno != 6:
|
|
raise e
|
|
else:
|
|
data = -1
|
|
# There are three options:
|
|
# 1) data == cur; @cur is in data
|
|
# 2) data > cur; @cur is in a hole, next data at @data
|
|
# 3) data < 0; either @cur is in trailing hole, or @cur is beyond EOF.
|
|
if data < 0:
|
|
# case 3
|
|
inData = False
|
|
eof = os.lseek(fd, 0, os.SEEK_END)
|
|
if (eof < cur):
|
|
raise RuntimeError("Current position in file after EOF: %d" % cur)
|
|
sectionLen = eof - cur
|
|
else:
|
|
if (data > cur):
|
|
# case 2
|
|
inData = False
|
|
sectionLen = data - cur
|
|
else:
|
|
# case 1
|
|
inData = True
|
|
|
|
# We don't know where does the next hole start. Let's find out.
|
|
# Here we get the same options as above
|
|
hole = os.lseek(fd, data, os.SEEK_HOLE)
|
|
if hole < 0:
|
|
# case 3. But wait a second. There is always a trailing hole.
|
|
# Do the best what we can here
|
|
raise RuntimeError("No trailing hole")
|
|
|
|
if (hole == data):
|
|
# case 1. Again, this is suspicious. The reason we are here is
|
|
# because we are in data. But at the same time we are in a
|
|
# hole. WAT?
|
|
raise RuntimeError("Impossible happened")
|
|
else:
|
|
# case 2
|
|
sectionLen = hole - data
|
|
os.lseek(fd, cur, os.SEEK_SET)
|
|
return [inData, sectionLen]
|
|
|
|
|
|
def download(vol: libvirt.virStorageVol, st: libvirt.virStream, filename: str) -> None:
|
|
offset = 0
|
|
length = 0
|
|
|
|
fd = os.open(filename, os.O_WRONLY | os.O_CREAT | os.O_TRUNC, mode=0o0660)
|
|
vol.download(st, offset, length, libvirt.VIR_STORAGE_VOL_DOWNLOAD_SPARSE_STREAM)
|
|
st.sparseRecvAll(bytesWriteHandler, recvSkipHandler, fd)
|
|
|
|
os.close(fd)
|
|
|
|
|
|
def upload(vol: libvirt.virStorageVol, st: libvirt.virStream, filename: str) -> None:
|
|
offset = 0
|
|
length = 0
|
|
|
|
fd = os.open(filename, os.O_RDONLY)
|
|
vol.upload(st, offset, length, libvirt.VIR_STORAGE_VOL_UPLOAD_SPARSE_STREAM)
|
|
st.sparseSendAll(bytesReadHandler, holeHandler, sendSkipHandler, fd)
|
|
|
|
os.close(fd)
|
|
|
|
|
|
# main
|
|
parser = ArgumentParser(description=__doc__)
|
|
parser.add_argument("uri")
|
|
group = parser.add_mutually_exclusive_group(required=True)
|
|
group.add_argument("--upload", action="store_const", const=upload, dest="operation")
|
|
group.add_argument("--download", action="store_const", const=download, dest="operation")
|
|
parser.add_argument("volume")
|
|
parser.add_argument("file")
|
|
args = parser.parse_args()
|
|
|
|
|
|
conn = libvirt.open(args.uri)
|
|
vol = conn.storageVolLookupByKey(args.volume)
|
|
|
|
st = conn.newStream()
|
|
|
|
args.operation(vol, st, args.file)
|
|
|
|
st.finish()
|
|
conn.close()
|