def prepare_rootfs_ext(self, rootfs, oe_builddir, rootfs_dir,
                           native_sysroot, pseudo):
        """
        Prepare content for an ext2/3/4 rootfs partition.
        """
        du_cmd = "du -ks %s" % rootfs_dir
        out = exec_cmd(du_cmd)
        actual_rootfs_size = int(out.split()[0])

        rootfs_size = self.get_rootfs_size(actual_rootfs_size)

        with open(rootfs, 'w') as sparse:
            os.ftruncate(sparse.fileno(), rootfs_size * 1024)

        extraopts = self.mkfs_extraopts or "-F -i 8192"

        label_str = ""
        if self.label:
            label_str = "-L %s" % self.label

        mkfs_cmd = "mkfs.%s %s %s %s -d %s" % \
            (self.fstype, extraopts, rootfs, label_str, rootfs_dir)
        exec_native_cmd(mkfs_cmd, native_sysroot, pseudo=pseudo)

        mkfs_cmd = "fsck.%s -pvfD %s" % (self.fstype, rootfs)
        exec_native_cmd(mkfs_cmd, native_sysroot, pseudo=pseudo)

    def prepare_rootfs_msdos(self, rootfs, oe_builddir, rootfs_dir,
                             native_sysroot, pseudo):
        """
        Prepare content for a msdos/vfat rootfs partition.
        """
        du_cmd = "du -bks %s" % rootfs_dir
        out = exec_cmd(du_cmd)
        blocks = int(out.split()[0])

        rootfs_size = self.get_rootfs_size(blocks)

        label_str = "-n boot"
        if self.label:
            label_str = "-n %s" % self.label

        size_str = ""
        if self.fstype == 'msdos':
            size_str = "-F 16" # FAT 16

        extraopts = self.mkfs_extraopts or '-S 512'

        dosfs_cmd = "mkdosfs %s %s %s -C %s %d" % \
                    (label_str, size_str, extraopts, rootfs, rootfs_size)
        exec_native_cmd(dosfs_cmd, native_sysroot)

        mcopy_cmd = "mcopy -i %s -s %s/* ::/" % (rootfs, rootfs_dir)
        exec_native_cmd(mcopy_cmd, native_sysroot)

        chmod_cmd = "chmod 644 %s" % rootfs
        exec_cmd(chmod_cmd)

    def finalize(self):
        """
        Finalize the disk image.

        For example, prepare the image to be bootable by e.g.
        creating and installing a bootloader configuration.
        """
        source_plugin = self.ks.bootloader.source
        disk_name = self.parts[0].disk
        if source_plugin:
            plugin = PluginMgr.get_plugins('source')[source_plugin]
            plugin.do_install_disk(self._image, disk_name, self, self.workdir,
                                   self.oe_builddir, self.bootimg_dir,
                                   self.kernel_dir, self.native_sysroot)

        full_path = self._image.path
        # Generate .bmap
        if self.bmap:
            logger.debug("Generating bmap file for %s", disk_name)
            python = os.path.join(self.native_sysroot, 'usr/bin/python3-native/python3')
            bmaptool = os.path.join(self.native_sysroot, 'usr/bin/bmaptool')
            exec_native_cmd("%s %s create %s -o %s.bmap" % \
                            (python, bmaptool, full_path, full_path), self.native_sysroot)
        # Compress the image
        if self.compressor:
            logger.debug("Compressing disk %s with %s", disk_name, self.compressor)
            exec_cmd("%s %s" % (self.compressor, full_path))

    def prepare_empty_partition_msdos(self, rootfs, oe_builddir,
                                      native_sysroot):
        """
        Prepare an empty vfat partition.
        """
        blocks = self.disk_size

        label_str = "-n boot"
        if self.label:
            label_str = "-n %s" % self.label

        size_str = ""
        if self.fstype == 'msdos':
            size_str = "-F 16" # FAT 16

        extraopts = self.mkfs_extraopts or '-S 512'

        dosfs_cmd = "mkdosfs %s -i %s %s %s -C %s %d" % \
                    (label_str, self.fsuuid, extraopts, size_str, rootfs,
                     blocks)

        exec_native_cmd(dosfs_cmd, native_sysroot)

        chmod_cmd = "chmod 644 %s" % rootfs
        exec_cmd(chmod_cmd)

 def prepare_rootfs_squashfs(self, rootfs, oe_builddir, rootfs_dir,
                             native_sysroot, pseudo):
     """
     Prepare content for a squashfs rootfs partition.
     """
     squashfs_cmd = "mksquashfs %s %s -noappend" % \
                    (rootfs_dir, rootfs)
     exec_native_cmd(squashfs_cmd, native_sysroot, pseudo=pseudo)

 def prepare_rootfs_squashfs(self, rootfs, oe_builddir, rootfs_dir,
                             native_sysroot, pseudo):
     """
     Prepare content for a squashfs rootfs partition.
     """
     extraopts = self.mkfs_extraopts or '-noappend'
     squashfs_cmd = "mksquashfs %s %s %s" % \
                    (rootfs_dir, rootfs, extraopts)
     exec_native_cmd(squashfs_cmd, native_sysroot, pseudo=pseudo)

    def prepare_swap_partition(self, cr_workdir, oe_builddir, native_sysroot):
        """
        Prepare a swap partition.
        """
        path = "%s/fs.%s" % (cr_workdir, self.fstype)

        with open(path, 'w') as sparse:
            os.ftruncate(sparse.fileno(), self.size * 1024)

        import uuid
        label_str = ""
        if self.label:
            label_str = "-L %s" % self.label
        mkswap_cmd = "mkswap %s -U %s %s" % (label_str, str(uuid.uuid1()), path)
        exec_native_cmd(mkswap_cmd, native_sysroot)

    def prepare_empty_partition_btrfs(self, rootfs, oe_builddir,
                                      native_sysroot):
        """
        Prepare an empty btrfs partition.
        """
        size = self.disk_size
        with open(rootfs, 'w') as sparse:
            os.ftruncate(sparse.fileno(), size * 1024)

        label_str = ""
        if self.label:
            label_str = "-L %s" % self.label

        mkfs_cmd = "mkfs.%s -b %d %s %s" % \
            (self.fstype, self.size * 1024, label_str, rootfs)
        exec_native_cmd(mkfs_cmd, native_sysroot)

    def prepare_empty_partition_ext(self, rootfs, oe_builddir,
                                    native_sysroot):
        """
        Prepare an empty ext2/3/4 partition.
        """
        size = self.disk_size
        with open(rootfs, 'w') as sparse:
            os.ftruncate(sparse.fileno(), size * 1024)

        extraopts = self.mkfs_extraopts or "-i 8192"

        label_str = ""
        if self.label:
            label_str = "-L %s" % self.label

        mkfs_cmd = "mkfs.%s -F %s %s %s" % \
            (self.fstype, extraopts, label_str, rootfs)
        exec_native_cmd(mkfs_cmd, native_sysroot)

    def prepare_rootfs_btrfs(self, rootfs, oe_builddir, rootfs_dir,
                             native_sysroot, pseudo):
        """
        Prepare content for a btrfs rootfs partition.
        """
        du_cmd = "du -ks %s" % rootfs_dir
        out = exec_cmd(du_cmd)
        actual_rootfs_size = int(out.split()[0])

        rootfs_size = self.get_rootfs_size(actual_rootfs_size)

        with open(rootfs, 'w') as sparse:
            os.ftruncate(sparse.fileno(), rootfs_size * 1024)

        label_str = ""
        if self.label:
            label_str = "-L %s" % self.label

        mkfs_cmd = "mkfs.%s -b %d -r %s %s %s -U %s %s" % \
            (self.fstype, rootfs_size * 1024, rootfs_dir, label_str,
             self.mkfs_extraopts, self.fsuuid, rootfs)
        exec_native_cmd(mkfs_cmd, native_sysroot, pseudo=pseudo)

    def _create_partition(self, device, parttype, fstype, start, size):
        """ Create a partition on an image described by the 'device' object. """

        # Start is included to the size so we need to substract one from the end.
        end = start + size - 1
        logger.debug("Added '%s' partition, sectors %d-%d, size %d sectors",
                     parttype, start, end, size)

        cmd = "parted -s %s unit s mkpart %s" % (device, parttype)
        if fstype:
            cmd += " %s" % fstype
        cmd += " %d %d" % (start, end)

        return exec_native_cmd(cmd, self.native_sysroot)

    def do_install_disk(cls, disk, disk_name, creator, workdir, oe_builddir,
                        bootimg_dir, kernel_dir, native_sysroot):
        """
        Called after all partitions have been prepared and assembled into a
        disk image.  In this case, we insert/modify the MBR using isohybrid
        utility for booting via BIOS from disk storage devices.
        """

        iso_img = "%s.p1" % disk.path
        full_path = creator._full_path(workdir, disk_name, "direct")
        full_path_iso = creator._full_path(workdir, disk_name, "iso")

        isohybrid_cmd = "isohybrid -u %s" % iso_img
        logger.debug("running command: %s", isohybrid_cmd)
        exec_native_cmd(isohybrid_cmd, native_sysroot)

        # Replace the image created by direct plugin with the one created by
        # mkisofs command. This is necessary because the iso image created by
        # mkisofs has a very specific MBR is system area of the ISO image, and
        # direct plugin adds and configures an another MBR.
        logger.debug("Replaceing the image created by direct plugin\n")
        os.remove(disk.path)
        shutil.copy2(iso_img, full_path_iso)
        shutil.copy2(full_path_iso, full_path)

#.........这里部分代码省略.........
                    if not os.path.exists(grub_src):
                        raise WicError("Grub loader %s is not found in %s. "
                                       "Please build grub-efi first" % (grub_image, deploy_dir))
                    shutil.copy(grub_src, grub_target)

                if not os.path.isfile(os.path.join(target_dir, "boot.cfg")):
                    cls.do_configure_grubefi(part, creator, target_dir)

            else:
                raise WicError("unrecognized bootimg-efi loader: %s" %
                               source_params['loader'])
        except KeyError:
            raise WicError("bootimg-efi requires a loader, none specified")

        # Create efi.img that contains bootloader files for EFI booting
        # if ISODIR didn't exist or didn't contains it
        if os.path.isfile("%s/efi.img" % img_iso_dir):
            install_cmd = "install -m 0644 %s/efi.img %s/efi.img" % \
                (img_iso_dir, isodir)
            exec_cmd(install_cmd)
        else:
            du_cmd = "du -bks %s/EFI" % isodir
            out = exec_cmd(du_cmd)
            blocks = int(out.split()[0])
            # Add some extra space for file system overhead
            blocks += 100
            logger.debug("Added 100 extra blocks to %s to get to %d "
                         "total blocks", part.mountpoint, blocks)

            # dosfs image for EFI boot
            bootimg = "%s/efi.img" % isodir

            dosfs_cmd = 'mkfs.vfat -n "EFIimg" -S 512 -C %s %d' \
                        % (bootimg, blocks)
            exec_native_cmd(dosfs_cmd, native_sysroot)

            mmd_cmd = "mmd -i %s ::/EFI" % bootimg
            exec_native_cmd(mmd_cmd, native_sysroot)

            mcopy_cmd = "mcopy -i %s -s %s/EFI/* ::/EFI/" \
                        % (bootimg, isodir)
            exec_native_cmd(mcopy_cmd, native_sysroot)

            chmod_cmd = "chmod 644 %s" % bootimg
            exec_cmd(chmod_cmd)

        # Prepare files for legacy boot
        syslinux_dir = get_bitbake_var("STAGING_DATADIR")
        if not syslinux_dir:
            raise WicError("Couldn't find STAGING_DATADIR, exiting.")

        if os.path.exists("%s/isolinux" % isodir):
            shutil.rmtree("%s/isolinux" % isodir)

        install_cmd = "install -d %s/isolinux" % isodir
        exec_cmd(install_cmd)

        cls.do_configure_syslinux(creator, cr_workdir)

        install_cmd = "install -m 444 %s/syslinux/ldlinux.sys " % syslinux_dir
        install_cmd += "%s/isolinux/ldlinux.sys" % isodir
        exec_cmd(install_cmd)

        install_cmd = "install -m 444 %s/syslinux/isohdpfx.bin " % syslinux_dir
        install_cmd += "%s/isolinux/isohdpfx.bin" % isodir
        exec_cmd(install_cmd)

        install_cmd = "install -m 644 %s/syslinux/isolinux.bin " % syslinux_dir
        install_cmd += "%s/isolinux/isolinux.bin" % isodir
        exec_cmd(install_cmd)

        install_cmd = "install -m 644 %s/syslinux/ldlinux.c32 " % syslinux_dir
        install_cmd += "%s/isolinux/ldlinux.c32" % isodir
        exec_cmd(install_cmd)

        #create ISO image
        iso_img = "%s/tempiso_img.iso" % cr_workdir
        iso_bootimg = "isolinux/isolinux.bin"
        iso_bootcat = "isolinux/boot.cat"
        efi_img = "efi.img"

        mkisofs_cmd = "mkisofs -V %s " % part.label
        mkisofs_cmd += "-o %s -U " % iso_img
        mkisofs_cmd += "-J -joliet-long -r -iso-level 2 -b %s " % iso_bootimg
        mkisofs_cmd += "-c %s -no-emul-boot -boot-load-size 4 " % iso_bootcat
        mkisofs_cmd += "-boot-info-table -eltorito-alt-boot "
        mkisofs_cmd += "-eltorito-platform 0xEF -eltorito-boot %s " % efi_img
        mkisofs_cmd += "-no-emul-boot %s " % isodir

        logger.debug("running command: %s", mkisofs_cmd)
        exec_native_cmd(mkisofs_cmd, native_sysroot)

        shutil.rmtree(isodir)

        du_cmd = "du -Lbks %s" % iso_img
        out = exec_cmd(du_cmd)
        isoimg_size = int(out.split()[0])

        part.size = isoimg_size
        part.source_file = iso_img

    def do_prepare_partition(cls, part, source_params, creator, cr_workdir,
                             oe_builddir, bootimg_dir, kernel_dir,
                             rootfs_dir, native_sysroot):
        """
        Called to do the actual content population for a partition i.e. it
        'prepares' the partition to be incorporated into the image.
        In this case, prepare content for an EFI (grub) boot partition.
        """
        if not kernel_dir:
            kernel_dir = get_bitbake_var("DEPLOY_DIR_IMAGE")
            if not kernel_dir:
                raise WicError("Couldn't find DEPLOY_DIR_IMAGE, exiting")

        staging_kernel_dir = kernel_dir

        hdddir = "%s/hdd/boot" % cr_workdir

        install_cmd = "install -m 0644 %s/bzImage %s/bzImage" % \
            (staging_kernel_dir, hdddir)
        exec_cmd(install_cmd)


        try:
            if source_params['loader'] == 'grub-efi':
                shutil.copyfile("%s/hdd/boot/EFI/BOOT/grub.cfg" % cr_workdir,
                                "%s/grub.cfg" % cr_workdir)
                for mod in [x for x in os.listdir(kernel_dir) if x.startswith("grub-efi-")]:
                    cp_cmd = "cp %s/%s %s/EFI/BOOT/%s" % (kernel_dir, mod, hdddir, mod[9:])
                    exec_cmd(cp_cmd, True)
                shutil.move("%s/grub.cfg" % cr_workdir,
                            "%s/hdd/boot/EFI/BOOT/grub.cfg" % cr_workdir)
            elif source_params['loader'] == 'systemd-boot':
                for mod in [x for x in os.listdir(kernel_dir) if x.startswith("systemd-")]:
                    cp_cmd = "cp %s/%s %s/EFI/BOOT/%s" % (kernel_dir, mod, hdddir, mod[8:])
                    exec_cmd(cp_cmd, True)
            else:
                raise WicError("unrecognized bootimg-efi loader: %s" %
                               source_params['loader'])
        except KeyError:
            raise WicError("bootimg-efi requires a loader, none specified")

        startup = os.path.join(kernel_dir, "startup.nsh")
        if os.path.exists(startup):
            cp_cmd = "cp %s %s/" % (startup, hdddir)
            exec_cmd(cp_cmd, True)

        du_cmd = "du -bks %s" % hdddir
        out = exec_cmd(du_cmd)
        blocks = int(out.split()[0])

        extra_blocks = part.get_extra_block_count(blocks)

        if extra_blocks < BOOTDD_EXTRA_SPACE:
            extra_blocks = BOOTDD_EXTRA_SPACE

        blocks += extra_blocks

        logger.debug("Added %d extra blocks to %s to get to %d total blocks",
                     extra_blocks, part.mountpoint, blocks)

        # dosfs image, created by mkdosfs
        bootimg = "%s/boot.img" % cr_workdir

        dosfs_cmd = "mkdosfs -n efi -i %s -C %s %d" % \
                    (part.fsuuid, bootimg, blocks)
        exec_native_cmd(dosfs_cmd, native_sysroot)

        mcopy_cmd = "mcopy -i %s -s %s/* ::/" % (bootimg, hdddir)
        exec_native_cmd(mcopy_cmd, native_sysroot)

        chmod_cmd = "chmod 644 %s" % bootimg
        exec_cmd(chmod_cmd)

        du_cmd = "du -Lbks %s" % bootimg
        out = exec_cmd(du_cmd)
        bootimg_size = out.split()[0]

        part.size = int(bootimg_size)
        part.source_file = bootimg

    def create(self):
        logger.debug("Creating sparse file %s", self.path)
        with open(self.path, 'w') as sparse:
            os.ftruncate(sparse.fileno(), self.min_size)

        logger.debug("Initializing partition table for %s", self.path)
        exec_native_cmd("parted -s %s mklabel %s" %
                        (self.path, self.ptable_format), self.native_sysroot)

        logger.debug("Set disk identifier %x", self.identifier)
        with open(self.path, 'r+b') as img:
            img.seek(0x1B8)
            img.write(self.identifier.to_bytes(4, 'little'))

        logger.debug("Creating partitions")

        for part in self.partitions:
            if part.num == 0:
                continue

            if self.ptable_format == "msdos" and part.num == 5:
                # Create an extended partition (note: extended
                # partition is described in MBR and contains all
                # logical partitions). The logical partitions save a
                # sector for an EBR just before the start of a
                # partition. The extended partition must start one
                # sector before the start of the first logical
                # partition. This way the first EBR is inside of the
                # extended partition. Since the extended partitions
                # starts a sector before the first logical partition,
                # add a sector at the back, so that there is enough
                # room for all logical partitions.
                self._create_partition(self.path, "extended",
                                       None, part.start - 1,
                                       self.offset - part.start + 1)

            if part.fstype == "swap":
                parted_fs_type = "linux-swap"
            elif part.fstype == "vfat":
                parted_fs_type = "fat32"
            elif part.fstype == "msdos":
                parted_fs_type = "fat16"
                if not part.system_id:
                    part.system_id = '0x6' # FAT16
            else:
                # Type for ext2/ext3/ext4/btrfs
                parted_fs_type = "ext2"

            # Boot ROM of OMAP boards require vfat boot partition to have an
            # even number of sectors.
            if part.mountpoint == "/boot" and part.fstype in ["vfat", "msdos"] \
               and part.size_sec % 2:
                logger.debug("Subtracting one sector from '%s' partition to "
                             "get even number of sectors for the partition",
                             part.mountpoint)
                part.size_sec -= 1

            self._create_partition(self.path, part.type,
                                   parted_fs_type, part.start, part.size_sec)

            if part.part_name:
                logger.debug("partition %d: set name to %s",
                             part.num, part.part_name)
                exec_native_cmd("sgdisk --change-name=%d:%s %s" % \
                                         (part.num, part.part_name,
                                          self.path), self.native_sysroot)

            if part.part_type:
                logger.debug("partition %d: set type UID to %s",
                             part.num, part.part_type)
                exec_native_cmd("sgdisk --typecode=%d:%s %s" % \
                                         (part.num, part.part_type,
                                          self.path), self.native_sysroot)

            if part.uuid and self.ptable_format == "gpt":
                logger.debug("partition %d: set UUID to %s",
                             part.num, part.uuid)
                exec_native_cmd("sgdisk --partition-guid=%d:%s %s" % \
                                (part.num, part.uuid, self.path),
                                self.native_sysroot)

            if part.label and self.ptable_format == "gpt":
                logger.debug("partition %d: set name to %s",
                             part.num, part.label)
                exec_native_cmd("parted -s %s name %d %s" % \
                                (self.path, part.num, part.label),
                                self.native_sysroot)

            if part.active:
                flag_name = "legacy_boot" if self.ptable_format == 'gpt' else "boot"
                logger.debug("Set '%s' flag for partition '%s' on disk '%s'",
                             flag_name, part.num, self.path)
                exec_native_cmd("parted -s %s set %d %s on" % \
                                (self.path, part.num, flag_name),
                                self.native_sysroot)
            if part.system_id:
                exec_native_cmd("sfdisk --part-type %s %s %s" % \
                                (self.path, part.num, part.system_id),
                                self.native_sysroot)

    def do_prepare_partition(cls, part, source_params, creator, cr_workdir,
                             oe_builddir, bootimg_dir, kernel_dir,
                             rootfs_dir, native_sysroot):
        """
        Called to do the actual content population for a partition i.e. it
        'prepares' the partition to be incorporated into the image.
        In this case, prepare content for legacy bios boot partition.
        """
        bootimg_dir = cls._get_bootimg_dir(bootimg_dir, 'syslinux')

        staging_kernel_dir = kernel_dir

        hdddir = "%s/hdd/boot" % cr_workdir

        cmds = ("install -m 0644 %s/bzImage %s/vmlinuz" %
                (staging_kernel_dir, hdddir),
                "install -m 444 %s/syslinux/ldlinux.sys %s/ldlinux.sys" %
                (bootimg_dir, hdddir),
                "install -m 0644 %s/syslinux/vesamenu.c32 %s/vesamenu.c32" %
                (bootimg_dir, hdddir),
                "install -m 444 %s/syslinux/libcom32.c32 %s/libcom32.c32" %
                (bootimg_dir, hdddir),
                "install -m 444 %s/syslinux/libutil.c32 %s/libutil.c32" %
                (bootimg_dir, hdddir))

        for install_cmd in cmds:
            exec_cmd(install_cmd)

        du_cmd = "du -bks %s" % hdddir
        out = exec_cmd(du_cmd)
        blocks = int(out.split()[0])

        extra_blocks = part.get_extra_block_count(blocks)

        if extra_blocks < BOOTDD_EXTRA_SPACE:
            extra_blocks = BOOTDD_EXTRA_SPACE

        blocks += extra_blocks

        logger.debug("Added %d extra blocks to %s to get to %d total blocks",
                     extra_blocks, part.mountpoint, blocks)

        # dosfs image, created by mkdosfs
        bootimg = "%s/boot%s.img" % (cr_workdir, part.lineno)

        dosfs_cmd = "mkdosfs -n boot -i %s -S 512 -C %s %d" % \
                    (part.fsuuid, bootimg, blocks)
        exec_native_cmd(dosfs_cmd, native_sysroot)

        mcopy_cmd = "mcopy -i %s -s %s/* ::/" % (bootimg, hdddir)
        exec_native_cmd(mcopy_cmd, native_sysroot)

        syslinux_cmd = "syslinux %s" % bootimg
        exec_native_cmd(syslinux_cmd, native_sysroot)

        chmod_cmd = "chmod 644 %s" % bootimg
        exec_cmd(chmod_cmd)

        du_cmd = "du -Lbks %s" % bootimg
        out = exec_cmd(du_cmd)
        bootimg_size = out.split()[0]

        part.size = int(bootimg_size)
        part.source_file = bootimg