1#!/usr/bin/env python3 2# group: quick 3# 4# Tests converting qcow2 compressed to NBD 5# 6# Copyright (c) 2020 Nir Soffer <nirsof@gmail.com> 7# 8# This program is free software; you can redistribute it and/or modify 9# it under the terms of the GNU General Public License as published by 10# the Free Software Foundation; either version 2 of the License, or 11# (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program. If not, see <http://www.gnu.org/licenses/>. 20# 21# owner=nirsof@gmail.com 22 23import io 24import tarfile 25 26import iotests 27 28from iotests import ( 29 file_path, 30 qemu_img, 31 qemu_img_check, 32 qemu_img_create, 33 qemu_img_log, 34 qemu_img_measure, 35 qemu_io, 36 qemu_nbd_popen, 37 img_info_log, 38) 39 40iotests.script_initialize(supported_fmts=["qcow2"]) 41 42# Create source disk. Using qcow2 to enable strict comparing later, and 43# avoid issues with random filesystem on CI environment. 44src_disk = file_path("disk.qcow2") 45qemu_img_create("-f", iotests.imgfmt, src_disk, "1g") 46qemu_io("-f", iotests.imgfmt, "-c", "write 1m 64k", src_disk) 47 48# The use case is writing qcow2 image directly into an ova file, which 49# is a tar file with specific layout. This is tricky since we don't know the 50# size of the image before compressing, so we have to do: 51# 1. Add an ovf file. 52# 2. Find the offset of the next member data. 53# 3. Make room for image data, allocating for the worst case. 54# 4. Write compressed image data into the tar. 55# 5. Add a tar entry with the actual image size. 56# 6. Shrink the tar to the actual size, aligned to 512 bytes. 57 58tar_file = file_path("test.ova") 59 60with tarfile.open(tar_file, "w") as tar: 61 62 # 1. Add an ovf file. 63 64 ovf_data = b"<xml/>" 65 ovf = tarfile.TarInfo("vm.ovf") 66 ovf.size = len(ovf_data) 67 tar.addfile(ovf, io.BytesIO(ovf_data)) 68 69 # 2. Find the offset of the next member data. 70 71 offset = tar.fileobj.tell() + 512 72 73 # 3. Make room for image data, allocating for the worst case. 74 75 measure = qemu_img_measure("-O", "qcow2", src_disk) 76 tar.fileobj.truncate(offset + measure["required"]) 77 78 # 4. Write compressed image data into the tar. 79 80 nbd_sock = file_path("nbd-sock", base_dir=iotests.sock_dir) 81 nbd_uri = "nbd+unix:///exp?socket=" + nbd_sock 82 83 # Use raw format to allow creating qcow2 directly into tar file. 84 with qemu_nbd_popen( 85 "--socket", nbd_sock, 86 "--export-name", "exp", 87 "--format", "raw", 88 "--offset", str(offset), 89 tar_file): 90 91 iotests.log("=== Target image info ===") 92 # Not img_info_log as it enforces imgfmt, but now we print info on raw 93 qemu_img_log("info", nbd_uri) 94 95 qemu_img( 96 "convert", 97 "-f", iotests.imgfmt, 98 "-O", "qcow2", 99 "-c", 100 src_disk, 101 nbd_uri) 102 103 iotests.log("=== Converted image info ===") 104 img_info_log(nbd_uri) 105 106 iotests.log("=== Converted image check ===") 107 qemu_img_log("check", nbd_uri) 108 109 iotests.log("=== Comparing to source disk ===") 110 qemu_img_log("compare", src_disk, nbd_uri) 111 112 actual_size = qemu_img_check(nbd_uri)["image-end-offset"] 113 114 # 5. Add a tar entry with the actual image size. 115 116 disk = tarfile.TarInfo("disk") 117 disk.size = actual_size 118 tar.addfile(disk) 119 120 # 6. Shrink the tar to the actual size, aligned to 512 bytes. 121 122 tar_size = offset + (disk.size + 511) & ~511 123 tar.fileobj.seek(tar_size) 124 tar.fileobj.truncate(tar_size) 125 126with tarfile.open(tar_file) as tar: 127 members = [{"name": m.name, "size": m.size, "offset": m.offset_data} 128 for m in tar] 129 iotests.log("=== OVA file contents ===") 130 iotests.log(members) 131