xemu/tests/qemu-iotests/044
Max Reitz 68474776f3 iotests: Different iterator behavior in Python 3
In Python 3, several functions now return iterators instead of lists.
This includes range(), items(), map(), and filter().  This means that if
we really want a list, we have to wrap those instances with list().  But
then again, the two instances where this is the case for map() and
filter(), there are shorter expressions which work without either
function.

On the other hand, sometimes we do just want an iterator, in which case
we have sometimes used xrange() and iteritems() which no longer exist in
Python 3.  Just change these calls to be range() and items(), works in
both Python 2 and 3, and is really what we want in 3 (which is what
matters).  But because it is so simple to do (and to find and remove
once we completely switch to Python 3), make range() be an alias for
xrange() in the two affected tests (044 and 163).

In one instance, we only wanted the first instance of the result of a
filter() call.  Instead of using next(filter()) which would work only in
Python 3, or list(filter())[0] which would work everywhere but is a bit
weird, this instance is changed to use a generator expression with a
next() wrapped around, which works both in 2.7 and 3.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20181022135307.14398-6-mreitz@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-10-30 21:11:52 -03:00

122 lines
3.8 KiB
Python
Executable File

#!/usr/bin/env python
#
# Tests growing a large refcount table.
#
# Copyright (C) 2012 Red Hat, Inc.
#
# This program 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 2 of the License, or
# (at your option) any later version.
#
# This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
#
import time
import os
import qcow2
from qcow2 import QcowHeader
import iotests
from iotests import qemu_img, qemu_img_verbose, qemu_io
import struct
import subprocess
import sys
if sys.version_info.major == 2:
range = xrange
test_img = os.path.join(iotests.test_dir, 'test.img')
class TestRefcountTableGrowth(iotests.QMPTestCase):
'''Abstract base class for image mirroring test cases'''
def preallocate(self, name):
fd = open(name, "r+b")
try:
off_reftable = 512
off_refblock = off_reftable + (512 * 512)
off_l1 = off_refblock + (512 * 512 * 64)
off_l2 = off_l1 + (512 * 512 * 4 * 8)
off_data = off_l2 + (512 * 512 * 4 * 512)
# Write a new header
h = QcowHeader(fd)
h.refcount_table_offset = off_reftable
h.refcount_table_clusters = 512
h.l1_table_offset = off_l1
h.l1_size = 512 * 512 * 4
h.update(fd)
# Write a refcount table
fd.seek(off_reftable)
for i in range(0, h.refcount_table_clusters):
sector = b''.join(struct.pack('>Q',
off_refblock + i * 64 * 512 + j * 512)
for j in range(0, 64))
fd.write(sector)
# Write the refcount blocks
assert(fd.tell() == off_refblock)
sector = b''.join(struct.pack('>H', 1) for j in range(0, 64 * 256))
for block in range(0, h.refcount_table_clusters):
fd.write(sector)
# Write the L1 table
assert(fd.tell() == off_l1)
assert(off_l2 + 512 * h.l1_size == off_data)
table = b''.join(struct.pack('>Q', (1 << 63) | off_l2 + 512 * j)
for j in range(0, h.l1_size))
fd.write(table)
# Write the L2 tables
assert(fd.tell() == off_l2)
img_file_size = h.refcount_table_clusters * 64 * 256 * 512
remaining = img_file_size - off_data
off = off_data
while remaining > 1024 * 512:
pytable = list((1 << 63) | off + 512 * j
for j in range(0, 1024))
table = struct.pack('>1024Q', *pytable)
fd.write(table)
remaining = remaining - 1024 * 512
off = off + 1024 * 512
table = b''.join(struct.pack('>Q', (1 << 63) | off + 512 * j)
for j in range(0, remaining // 512))
fd.write(table)
# Data
fd.truncate(img_file_size)
finally:
fd.close()
def setUp(self):
qemu_img('create', '-f', iotests.imgfmt, '-o', 'cluster_size=512', test_img, '16G')
self.preallocate(test_img)
pass
def tearDown(self):
os.remove(test_img)
pass
def test_grow_refcount_table(self):
qemu_io('-c', 'write 3800M 1M', test_img)
qemu_img_verbose('check' , test_img)
pass
if __name__ == '__main__':
iotests.main(supported_fmts=['qcow2'])