def do_unpack(cls, srcimg):
        srcimgsize = (misc.get_file_size(srcimg)) * 1024L * 1024L
        srcmnt = misc.mkdtemp("srcmnt")
        disk = fs_related.SparseLoopbackDisk(srcimg, srcimgsize)
        srcloop = PartitionedMount(srcmnt, skipformat = True)

        srcloop.add_disk('/dev/sdb', disk)
        srcloop.add_partition(srcimgsize/1024/1024, "/dev/sdb", "/", "ext3", boot=False)
        try:
            srcloop.mount()

        except errors.MountError:
            srcloop.cleanup()
            raise

        image = os.path.join(tempfile.mkdtemp(dir = "/var/tmp", prefix = "tmp"), "target.img")
        args = ['dd', "if=%s" % srcloop.partitions[0]['device'], "of=%s" % image]

        msger.info("`dd` image ...")
        rc = runner.show(args)
        srcloop.cleanup()
        shutil.rmtree(os.path.dirname(srcmnt), ignore_errors = True)

        if rc != 0:
            raise errors.CreatorError("Failed to dd")
        else:
            return image

    def do_chroot(cls, target):#chroot.py parse opts&args
        img = target
        imgsize = misc.get_file_size(img) * 1024L * 1024L
        imgtype = misc.get_image_type(img)
        if imgtype == "btrfsimg":
            fstype = "btrfs"
            myDiskMount = fs_related.BtrfsDiskMount
        elif imgtype in ("ext3fsimg", "ext4fsimg"):
            fstype = imgtype[:4]
            myDiskMount = fs_related.ExtDiskMount
        else:
            raise errors.CreatorError("Unsupported filesystem type: %s" % imgtype)

        extmnt = misc.mkdtemp()
        extloop = myDiskMount(fs_related.SparseLoopbackDisk(img, imgsize),
                                                         extmnt,
                                                         fstype,
                                                         4096,
                                                         "%s label" % fstype)
        try:
            extloop.mount()

        except errors.MountError:
            extloop.cleanup()
            shutil.rmtree(extmnt, ignore_errors = True)
            raise

        try:
            chroot.chroot(extmnt, None,  "/bin/env HOME=/root /bin/bash")
        except:
            raise errors.CreatorError("Failed to chroot to %s." %img)
        finally:
            chroot.cleanup_after_chroot("img", extloop, None, extmnt)

    def _mount_instroot(self, base_on=None):

        if base_on and os.path.isfile(base_on):
            self.__imgdir = os.path.dirname(base_on)
            imgname = os.path.basename(base_on)
            self._base_on(base_on)
            self._set_image_size(misc.get_file_size(self._image))

            # here, self._instloops must be []
            self._instloops.append({
                 "mountpoint": "/",
                 "label": self.name,
                 "name": imgname,
                 "size": self.__image_size or 4096L,
                 "fstype": self.__fstype or "ext3",
                 "extopts": None,
                 "loop": None
                 })

        self._check_imgdir()

        for loop in self._instloops:
            fstype = loop['fstype']
            mp = os.path.join(self._instroot, loop['mountpoint'].lstrip('/'))
            size = loop['size'] * 1024L * 1024L
            imgname = loop['name']

            if fstype in ("ext2", "ext3", "ext4"):
                MyDiskMount = fs.ExtDiskMount
            elif fstype == "btrfs":
                MyDiskMount = fs.BtrfsDiskMount
            elif fstype in ("vfat", "msdos"):
                MyDiskMount = fs.VfatDiskMount
            else:
                msger.error('Cannot support fstype: %s' % fstype)

            loop['loop'] = MyDiskMount(fs.SparseLoopbackDisk(
                                           os.path.join(self.__imgdir, imgname),
                                           size),
                                       mp,
                                       fstype,
                                       self._blocksize,
                                       loop['label'])

            if fstype in ("ext2", "ext3", "ext4"):
                loop['loop'].extopts = loop['extopts']

            try:
                msger.verbose('Mounting image "%s" on "%s"' % (imgname, mp))
                fs.makedirs(mp)
                loop['loop'].mount()
            except MountError, e:
                raise

    def do_chroot(cls, target, cmd=[]):
        if target.endswith('.tar'):
            import tarfile
            if tarfile.is_tarfile(target):
                LoopPlugin._do_chroot_tar(target, cmd)
                return
            else:
                raise errors.CreatorError("damaged tarball for loop images")

        img = target
        imgsize = misc.get_file_size(img) * 1024L * 1024L
        imgtype = misc.get_image_type(img)
        if imgtype == "btrfsimg":
            fstype = "btrfs"
            myDiskMount = fs_related.BtrfsDiskMount
        elif imgtype in ("ext3fsimg", "ext4fsimg"):
            fstype = imgtype[:4]
            myDiskMount = fs_related.ExtDiskMount
        else:
            raise errors.CreatorError("Unsupported filesystem type: %s" \
                                      % imgtype)

        extmnt = misc.mkdtemp()
        extloop = myDiskMount(fs_related.SparseLoopbackDisk(img, imgsize),
                                                         extmnt,
                                                         fstype,
                                                         4096,
                                                         "%s label" % fstype)
        try:
            extloop.mount()

        except errors.MountError:
            extloop.cleanup()
            shutil.rmtree(extmnt, ignore_errors=True)
            raise

        try:
            if len(cmd) != 0:
                cmdline = ' '.join(cmd)
            else:
                cmdline = "/bin/bash"
            envcmd = fs_related.find_binary_inchroot("env", extmnt)
            if envcmd:
                cmdline = "%s HOME=/root %s" % (envcmd, cmdline)
            chroot.chroot(extmnt, None, cmdline)
        except:
            raise errors.CreatorError("Failed to chroot to %s." % img)
        finally:
            chroot.cleanup_after_chroot("img", extloop, None, extmnt)

    def do_unpack(cls, srcimg):
        img = srcimg
        imgsize = misc.get_file_size(img) * 1024L * 1024L
        imgmnt = misc.mkdtemp()
        disk = fs_related.SparseLoopbackDisk(img, imgsize)
        imgloop = PartitionedMount(imgmnt, skipformat = True)
        imgloop.add_disk('/dev/sdb', disk)
        imgloop.add_partition(imgsize/1024/1024, "/dev/sdb", "/", "vfat", boot=False)
        try:
            imgloop.mount()
        except errors.MountError:
            imgloop.cleanup()
            raise

        # legacy LiveOS filesystem layout support, remove for F9 or F10
        if os.path.exists(imgmnt + "/squashfs.img"):
            squashimg = imgmnt + "/squashfs.img"
        else:
            squashimg = imgmnt + "/LiveOS/squashfs.img"

        tmpoutdir = misc.mkdtemp()
        # unsquashfs requires outdir mustn't exist
        shutil.rmtree(tmpoutdir, ignore_errors = True)
        misc.uncompress_squashfs(squashimg, tmpoutdir)

        try:
            # legacy LiveOS filesystem layout support, remove for F9 or F10
            if os.path.exists(tmpoutdir + "/os.img"):
                os_image = tmpoutdir + "/os.img"
            else:
                os_image = tmpoutdir + "/LiveOS/ext3fs.img"

            if not os.path.exists(os_image):
                raise errors.CreatorError("'%s' is not a valid live CD ISO : neither "
                                          "LiveOS/ext3fs.img nor os.img exist" %img)
            imgname = os.path.basename(srcimg)
            imgname = os.path.splitext(imgname)[0] + ".img"
            rtimage = os.path.join(tempfile.mkdtemp(dir = "/var/tmp", prefix = "tmp"), imgname)
            shutil.copyfile(os_image, rtimage)

        finally:
            imgloop.cleanup()
            shutil.rmtree(tmpoutdir, ignore_errors = True)
            shutil.rmtree(imgmnt, ignore_errors = True)

        return rtimage

    def do_chroot(cls, target, cmd=[]):
        os_image = cls.do_unpack(target)
        os_image_dir = os.path.dirname(os_image)

        # unpack image to target dir
        imgsize = misc.get_file_size(os_image) * 1024L * 1024L
        imgtype = misc.get_image_type(os_image)
        if imgtype == "btrfsimg":
            fstype = "btrfs"
            myDiskMount = fs_related.BtrfsDiskMount
        elif imgtype in ("ext3fsimg", "ext4fsimg"):
            fstype = imgtype[:4]
            myDiskMount = fs_related.ExtDiskMount
        else:
            raise errors.CreatorError("Unsupported filesystem type: %s" % fstype)

        extmnt = misc.mkdtemp()
        extloop = myDiskMount(fs_related.SparseLoopbackDisk(os_image, imgsize),
                              extmnt,
                              fstype,
                              4096,
                              "%s label" % fstype)
        try:
            extloop.mount()

        except errors.MountError:
            extloop.cleanup()
            shutil.rmtree(extmnt, ignore_errors = True)
            shutil.rmtree(os_image_dir, ignore_errors = True)
            raise

        try:
            if len(cmd) != 0:
                cmdline = ' '.join(cmd)
            else:
                cmdline = "/bin/bash"
            envcmd = fs_related.find_binary_inchroot("env", extmnt)
            if envcmd:
                cmdline = "%s HOME=/root %s" % (envcmd, cmdline)
            chroot.chroot(extmnt, None, cmdline)
        except:
            raise errors.CreatorError("Failed to chroot to %s." %target)
        finally:
            chroot.cleanup_after_chroot("img", extloop, os_image_dir, extmnt)

    def _create_usbimg(self, isodir):
        overlaysizemb = 64 #default
        #skipcompress = self.skip_compression?
        fstype = "vfat"
        homesizemb=0
        swapsizemb=0
        homefile="home.img"
        plussize=128
        kernelargs=None

        if fstype == 'vfat':
            if overlaysizemb > 2047:
                raise CreatorError("Can't have an overlay of 2048MB or "
                                   "greater on VFAT")

            if homesizemb > 2047:
                raise CreatorError("Can't have an home overlay of 2048MB or "
                                   "greater on VFAT")

            if swapsizemb > 2047:
                raise CreatorError("Can't have an swap overlay of 2048MB or "
                                   "greater on VFAT")

        livesize = misc.get_file_size(isodir + "/LiveOS")

        usbimgsize = (overlaysizemb + \
                      homesizemb + \
                      swapsizemb + \
                      livesize + \
                      plussize) * 1024L * 1024L

        disk = fs_related.SparseLoopbackDisk("%s/%s.usbimg" \
                                                 % (self._outdir, self.name),
                                             usbimgsize)
        usbmnt = self._mkdtemp("usb-mnt")
        usbloop = PartitionedMount(usbmnt)
        usbloop.add_disk('/dev/sdb', disk)

        usbloop.add_partition(usbimgsize/1024/1024,
                              "/dev/sdb",
                              "/",
                              fstype,
                              boot=True)

        usbloop.mount()

        try:
            fs_related.makedirs(usbmnt + "/LiveOS")

            if os.path.exists(isodir + "/LiveOS/squashfs.img"):
                shutil.copyfile(isodir + "/LiveOS/squashfs.img",
                                usbmnt + "/LiveOS/squashfs.img")
            else:
                fs_related.mksquashfs(os.path.dirname(self._image),
                                      usbmnt + "/LiveOS/squashfs.img")

            if os.path.exists(isodir + "/LiveOS/osmin.img"):
                shutil.copyfile(isodir + "/LiveOS/osmin.img",
                                usbmnt + "/LiveOS/osmin.img")

            if fstype == "vfat" or fstype == "msdos":
                uuid = usbloop.partitions[0]['mount'].uuid
                label = usbloop.partitions[0]['mount'].fslabel
                usblabel = "UUID=%s-%s" % (uuid[0:4], uuid[4:8])
                overlaysuffix = "-%s-%s-%s" % (label, uuid[0:4], uuid[4:8])
            else:
                diskmount = usbloop.partitions[0]['mount']
                usblabel = "UUID=%s" % diskmount.uuid
                overlaysuffix = "-%s-%s" % (diskmount.fslabel, diskmount.uuid)

            args = ['cp', "-Rf", isodir + "/isolinux", usbmnt + "/syslinux"]
            rc = runner.show(args)
            if rc:
                raise CreatorError("Can't copy isolinux directory %s" \
                                   % (isodir + "/isolinux/*"))

            if os.path.isfile("/usr/share/syslinux/isolinux.bin"):
                syslinux_path = "/usr/share/syslinux"
            elif  os.path.isfile("/usr/lib/syslinux/isolinux.bin"):
                syslinux_path = "/usr/lib/syslinux"
            else:
                raise CreatorError("syslinux not installed : "
                                   "cannot find syslinux installation path")

            for f in ("isolinux.bin", "vesamenu.c32"):
                path = os.path.join(syslinux_path, f)
                if os.path.isfile(path):
                    args = ['cp', path, usbmnt + "/syslinux/"]
                    rc = runner.show(args)
                    if rc:
                        raise CreatorError("Can't copy syslinux file " + path)
                else:
                    raise CreatorError("syslinux not installed: "
                                       "syslinux file %s not found" % path)

            fd = open(isodir + "/isolinux/isolinux.cfg", "r")
            text = fd.read()
            fd.close()
            pattern = re.compile('CDLABEL=[^ ]*')
            text = pattern.sub(usblabel, text)
#.........这里部分代码省略.........

    def do_chroot(cls, target, cmd=[]):
        img = target
        imgsize = misc.get_file_size(img) * 1024L * 1024L
        partedcmd = fs_related.find_binary_path("parted")
        disk = fs_related.SparseLoopbackDisk(img, imgsize)
        imgmnt = misc.mkdtemp()
        imgloop = PartitionedMount(imgmnt, skipformat = True)
        imgloop.add_disk('/dev/sdb', disk)
        img_fstype = "ext3"

        msger.info("Partition Table:")
        partnum = []
        for line in runner.outs([partedcmd, "-s", img, "print"]).splitlines():
            # no use strip to keep line output here
            if "Number" in line:
                msger.raw(line)
            if line.strip() and line.strip()[0].isdigit():
                partnum.append(line.strip()[0])
                msger.raw(line)

        rootpart = None
        if len(partnum) > 1:
            rootpart = msger.choice("please choose root partition", partnum)

        # Check the partitions from raw disk.
        # if choose root part, the mark it as mounted
        if rootpart:
            root_mounted = True
        else:
            root_mounted = False
        partition_mounts = 0
        for line in runner.outs([partedcmd,"-s",img,"unit","B","print"]).splitlines():
            line = line.strip()

            # Lines that start with number are the partitions,
            # because parted can be translated we can't refer to any text lines.
            if not line or not line[0].isdigit():
                continue

            # Some vars have extra , as list seperator.
            line = line.replace(",","")

            # Example of parted output lines that are handled:
            # Number  Start        End          Size         Type     File system     Flags
            #  1      512B         3400000511B  3400000000B  primary
            #  2      3400531968B  3656384511B  255852544B   primary  linux-swap(v1)
            #  3      3656384512B  3720347647B  63963136B    primary  fat16           boot, lba

            partition_info = re.split("\s+",line)

            size = partition_info[3].split("B")[0]

            if len(partition_info) < 6 or partition_info[5] in ["boot"]:
                # No filesystem can be found from partition line. Assuming
                # btrfs, because that is the only MeeGo fs that parted does
                # not recognize properly.
                # TODO: Can we make better assumption?
                fstype = "btrfs"
            elif partition_info[5] in ["ext2","ext3","ext4","btrfs"]:
                fstype = partition_info[5]
            elif partition_info[5] in ["fat16","fat32"]:
                fstype = "vfat"
            elif "swap" in partition_info[5]:
                fstype = "swap"
            else:
                raise errors.CreatorError("Could not recognize partition fs type '%s'." % partition_info[5])

            if rootpart and rootpart == line[0]:
                mountpoint = '/'
            elif not root_mounted and fstype in ["ext2","ext3","ext4","btrfs"]:
                # TODO: Check that this is actually the valid root partition from /etc/fstab
                mountpoint = "/"
                root_mounted = True
            elif fstype == "swap":
                mountpoint = "swap"
            else:
                # TODO: Assing better mount points for the rest of the partitions.
                partition_mounts += 1
                mountpoint = "/media/partition_%d" % partition_mounts

            if "boot" in partition_info:
                boot = True
            else:
                boot = False

            msger.verbose("Size: %s Bytes, fstype: %s, mountpoint: %s, boot: %s" % (size, fstype, mountpoint, boot))
            # TODO: add_partition should take bytes as size parameter.
            imgloop.add_partition((int)(size)/1024/1024, "/dev/sdb", mountpoint, fstype = fstype, boot = boot)

        try:
            imgloop.mount()

        except errors.MountError:
            imgloop.cleanup()
            raise

        try:
            if len(cmd) != 0:
                cmdline = ' '.join(cmd)
            else:
#.........这里部分代码省略.........