bootimg-pcbios-label.py: Workaround the label limitation of bootimg-pcbios

The bootimg-pcbios wic plugin in dunfell hardcodes the filesystem label
without taking into consideration the --label argument. This was
improved later on but it never landed in dunfell:

commit a79b5f0f2139bbd77df31704944630c8a5a0b562
Author: jbouchard <jeanbouch418@gmail.com>
Date:   Sun Jun 27 20:28:37 2021 -0400
Use the label provided when formating a dos partition

We workaround this by creating a version of this plugin that has this
change included and we will be using this new plugin until the
improvement (if at all) lands in dunfell.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

meta-ohos-core/scripts/lib/wic/plugins/source/bootimg-pcbios-label.py

+#
+# Copyright (c) 2014, Intel Corporation.
+#
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# DESCRIPTION
+# This implements the 'bootimg-pcbios-label' source plugin class for 'wic'
+#
+# AUTHORS
+# Tom Zanussi <tom.zanussi (at] linux.intel.com>
+#
+
+import logging
+import os
+import re
+
+from wic import WicError
+from wic.engine import get_custom_config
+from wic.pluginbase import SourcePlugin
+from wic.misc import (exec_cmd, exec_native_cmd,
+                      get_bitbake_var, BOOTDD_EXTRA_SPACE)
+
+logger = logging.getLogger('wic')
+
+class BootimgPcbiosLabelPlugin(SourcePlugin):
+    """
+    Create MBR boot partition and install syslinux on it.
+    """
+
+    name = 'bootimg-pcbios-label'
+
+    @classmethod
+    def _get_bootimg_dir(cls, bootimg_dir, dirname):
+        """
+        Check if dirname exists in default bootimg_dir or in STAGING_DIR.
+        """
+        staging_datadir = get_bitbake_var("STAGING_DATADIR")
+        for result in (bootimg_dir, staging_datadir):
+            if os.path.exists("%s/%s" % (result, dirname)):
+                return result
+
+        # STAGING_DATADIR is expanded with MLPREFIX if multilib is enabled
+        # but dependency syslinux is still populated to original STAGING_DATADIR
+        nonarch_datadir = re.sub('/[^/]*recipe-sysroot', '/recipe-sysroot', staging_datadir)
+        if os.path.exists(os.path.join(nonarch_datadir, dirname)):
+            return nonarch_datadir
+
+        raise WicError("Couldn't find correct bootimg_dir, exiting")
+
+    @classmethod
+    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 install the MBR.
+        """
+        bootimg_dir = cls._get_bootimg_dir(bootimg_dir, 'syslinux')
+        mbrfile = "%s/syslinux/" % bootimg_dir
+        if creator.ptable_format == 'msdos':
+            mbrfile += "mbr.bin"
+        elif creator.ptable_format == 'gpt':
+            mbrfile += "gptmbr.bin"
+        else:
+            raise WicError("Unsupported partition table: %s" %
+                           creator.ptable_format)
+
+        if not os.path.exists(mbrfile):
+            raise WicError("Couldn't find %s.  If using the -e option, do you "
+                           "have the right MACHINE set in local.conf?  If not, "
+                           "is the bootimg_dir path correct?" % mbrfile)
+
+        full_path = creator._full_path(workdir, disk_name, "direct")
+        logger.debug("Installing MBR on disk %s as %s with size %s bytes",
+                     disk_name, full_path, disk.min_size)
+
+        dd_cmd = "dd if=%s of=%s conv=notrunc" % (mbrfile, full_path)
+        exec_cmd(dd_cmd, native_sysroot)
+
+    @classmethod
+    def do_configure_partition(cls, part, source_params, creator, cr_workdir,
+                               oe_builddir, bootimg_dir, kernel_dir,
+                               native_sysroot):
+        """
+        Called before do_prepare_partition(), creates syslinux config
+        """
+        hdddir = "%s/hdd/boot" % cr_workdir
+
+        install_cmd = "install -d %s" % hdddir
+        exec_cmd(install_cmd)
+
+        bootloader = creator.ks.bootloader
+
+        custom_cfg = None
+        if bootloader.configfile:
+            custom_cfg = get_custom_config(bootloader.configfile)
+            if custom_cfg:
+                # Use a custom configuration for grub
+                syslinux_conf = custom_cfg
+                logger.debug("Using custom configuration file %s "
+                             "for syslinux.cfg", bootloader.configfile)
+            else:
+                raise WicError("configfile is specified but failed to "
+                               "get it from %s." % bootloader.configfile)
+
+        if not custom_cfg:
+            # Create syslinux configuration using parameters from wks file
+            splash = os.path.join(cr_workdir, "/hdd/boot/splash.jpg")
+            if os.path.exists(splash):
+                splashline = "menu background splash.jpg"
+            else:
+                splashline = ""
+
+            syslinux_conf = ""
+            syslinux_conf += "PROMPT 0\n"
+            syslinux_conf += "TIMEOUT " + str(bootloader.timeout) + "\n"
+            syslinux_conf += "\n"
+            syslinux_conf += "ALLOWOPTIONS 1\n"
+            syslinux_conf += "SERIAL 0 115200\n"
+            syslinux_conf += "\n"
+            if splashline:
+                syslinux_conf += "%s\n" % splashline
+            syslinux_conf += "DEFAULT boot\n"
+            syslinux_conf += "LABEL boot\n"
+
+            kernel = "/vmlinuz"
+            syslinux_conf += "KERNEL " + kernel + "\n"
+
+            syslinux_conf += "APPEND label=boot root=%s %s\n" % \
+                             (creator.rootdev, bootloader.append)
+
+        logger.debug("Writing syslinux config %s/hdd/boot/syslinux.cfg",
+                     cr_workdir)
+        cfg = open("%s/hdd/boot/syslinux.cfg" % cr_workdir, "w")
+        cfg.write(syslinux_conf)
+        cfg.close()
+
+    @classmethod
+    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
+
+        kernel = get_bitbake_var("KERNEL_IMAGETYPE")
+        if get_bitbake_var("INITRAMFS_IMAGE_BUNDLE") == "1":
+            if get_bitbake_var("INITRAMFS_IMAGE"):
+                kernel = "%s-%s.bin" % \
+                    (get_bitbake_var("KERNEL_IMAGETYPE"), get_bitbake_var("INITRAMFS_LINK_NAME"))
+
+        cmds = ("install -m 0644 %s/%s %s/vmlinuz" %
+                (staging_kernel_dir, kernel, 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)
+
+        label = part.label if part.label else "boot"
+
+        dosfs_cmd = "mkdosfs -n %s -i %s -S 512 -C %s %d" % \
+                    (label, 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