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|
# Copyright (c) 2013, Intel Corporation.
#
# SPDX-License-Identifier: GPL-2.0-only
#
# DESCRIPTION
# This module implements some basic help invocation functions along
# with the bulk of the help topic text for the OE Core Image Tools.
#
# AUTHORS
# Tom Zanussi <tom.zanussi (at] linux.intel.com>
#
import subprocess
import logging
from wic.pluginbase import PluginMgr, PLUGIN_TYPES
logger = logging.getLogger('wic')
def subcommand_error(args):
logger.info("invalid subcommand %s", args[0])
def display_help(subcommand, subcommands):
"""
Display help for subcommand.
"""
if subcommand not in subcommands:
return False
hlp = subcommands.get(subcommand, subcommand_error)[2]
if callable(hlp):
hlp = hlp()
pager = subprocess.Popen('less', stdin=subprocess.PIPE)
pager.communicate(hlp.encode('utf-8'))
return True
def wic_help(args, usage_str, subcommands):
"""
Subcommand help dispatcher.
"""
if args.help_topic == None or not display_help(args.help_topic, subcommands):
print(usage_str)
def get_wic_plugins_help():
"""
Combine wic_plugins_help with the help for every known
source plugin.
"""
result = wic_plugins_help
for plugin_type in PLUGIN_TYPES:
result += '\n\n%s PLUGINS\n\n' % plugin_type.upper()
for name, plugin in PluginMgr.get_plugins(plugin_type).items():
result += "\n %s plugin:\n" % name
if plugin.__doc__:
result += plugin.__doc__
else:
result += "\n %s is missing docstring\n" % plugin
return result
def invoke_subcommand(args, parser, main_command_usage, subcommands):
"""
Dispatch to subcommand handler borrowed from combo-layer.
Should use argparse, but has to work in 2.6.
"""
if not args.command:
logger.error("No subcommand specified, exiting")
parser.print_help()
return 1
elif args.command == "help":
wic_help(args, main_command_usage, subcommands)
elif args.command not in subcommands:
logger.error("Unsupported subcommand %s, exiting\n", args.command)
parser.print_help()
return 1
else:
subcmd = subcommands.get(args.command, subcommand_error)
usage = subcmd[1]
subcmd[0](args, usage)
##
# wic help and usage strings
##
wic_usage = """
Create a customized OpenEmbedded image
usage: wic [--version] | [--help] | [COMMAND [ARGS]]
Current 'wic' commands are:
help Show help for command or one of the topics (see below)
create Create a new OpenEmbedded image
list List available canned images and source plugins
Help topics:
overview wic overview - General overview of wic
plugins wic plugins - Overview and API
kickstart wic kickstart - wic kickstart reference
"""
wic_help_usage = """
usage: wic help <subcommand>
This command displays detailed help for the specified subcommand.
"""
wic_create_usage = """
Create a new OpenEmbedded image
usage: wic create <wks file or image name> [-o <DIRNAME> | --outdir <DIRNAME>]
[-e | --image-name] [-s, --skip-build-check] [-D, --debug]
[-r, --rootfs-dir] [-b, --bootimg-dir]
[-k, --kernel-dir] [-n, --native-sysroot] [-f, --build-rootfs]
[-c, --compress-with] [-m, --bmap]
This command creates an OpenEmbedded image based on the 'OE kickstart
commands' found in the <wks file>.
The -o option can be used to place the image in a directory with a
different name and location.
See 'wic help create' for more detailed instructions.
"""
wic_create_help = """
NAME
wic create - Create a new OpenEmbedded image
SYNOPSIS
wic create <wks file or image name> [-o <DIRNAME> | --outdir <DIRNAME>]
[-e | --image-name] [-s, --skip-build-check] [-D, --debug]
[-r, --rootfs-dir] [-b, --bootimg-dir]
[-k, --kernel-dir] [-n, --native-sysroot] [-f, --build-rootfs]
[-c, --compress-with] [-m, --bmap] [--no-fstab-update]
DESCRIPTION
This command creates an OpenEmbedded image based on the 'OE
kickstart commands' found in the <wks file>.
In order to do this, wic needs to know the locations of the
various build artifacts required to build the image.
Users can explicitly specify the build artifact locations using
the -r, -b, -k, and -n options. See below for details on where
the corresponding artifacts are typically found in a normal
OpenEmbedded build.
Alternatively, users can use the -e option to have 'wic' determine
those locations for a given image. If the -e option is used, the
user needs to have set the appropriate MACHINE variable in
local.conf, and have sourced the build environment.
The -e option is used to specify the name of the image to use the
artifacts from e.g. core-image-sato.
The -r option is used to specify the path to the /rootfs dir to
use as the .wks rootfs source.
The -b option is used to specify the path to the dir containing
the boot artifacts (e.g. /EFI or /syslinux dirs) to use as the
.wks bootimg source.
The -k option is used to specify the path to the dir containing
the kernel to use in the .wks bootimg.
The -n option is used to specify the path to the native sysroot
containing the tools to use to build the image.
The -f option is used to build rootfs by running "bitbake <image>"
The -s option is used to skip the build check. The build check is
a simple sanity check used to determine whether the user has
sourced the build environment so that the -e option can operate
correctly. If the user has specified the build artifact locations
explicitly, 'wic' assumes the user knows what he or she is doing
and skips the build check.
The -D option is used to display debug information detailing
exactly what happens behind the scenes when a create request is
fulfilled (or not, as the case may be). It enumerates and
displays the command sequence used, and should be included in any
bug report describing unexpected results.
When 'wic -e' is used, the locations for the build artifacts
values are determined by 'wic -e' from the output of the 'bitbake
-e' command given an image name e.g. 'core-image-minimal' and a
given machine set in local.conf. In that case, the image is
created as if the following 'bitbake -e' variables were used:
-r: IMAGE_ROOTFS
-k: STAGING_KERNEL_DIR
-n: STAGING_DIR_NATIVE
-b: empty (plugin-specific handlers must determine this)
If 'wic -e' is not used, the user needs to select the appropriate
value for -b (as well as -r, -k, and -n).
The -o option can be used to place the image in a directory with a
different name and location.
The -c option is used to specify compressor utility to compress
an image. gzip, bzip2 and xz compressors are supported.
The -m option is used to produce .bmap file for the image. This file
can be used to flash image using bmaptool utility.
The --no-fstab-update option is used to doesn't change fstab file. When
using this option the final fstab file will be same that in rootfs and
wic doesn't update file, e.g adding a new mount point. User can control
the fstab file content in base-files recipe.
"""
wic_list_usage = """
List available OpenEmbedded images and source plugins
usage: wic list images
wic list <image> help
wic list source-plugins
This command enumerates the set of available canned images as well as
help for those images. It also can be used to list of available source
plugins.
The first form enumerates all the available 'canned' images.
The second form lists the detailed help information for a specific
'canned' image.
The third form enumerates all the available --sources (source
plugins).
See 'wic help list' for more details.
"""
wic_list_help = """
NAME
wic list - List available OpenEmbedded images and source plugins
SYNOPSIS
wic list images
wic list <image> help
wic list source-plugins
DESCRIPTION
This command enumerates the set of available canned images as well
as help for those images. It also can be used to list available
source plugins.
The first form enumerates all the available 'canned' images.
These are actually just the set of .wks files that have been moved
into the /scripts/lib/wic/canned-wks directory).
The second form lists the detailed help information for a specific
'canned' image.
The third form enumerates all the available --sources (source
plugins). The contents of a given partition are driven by code
defined in 'source plugins'. Users specify a specific plugin via
the --source parameter of the partition .wks command. Normally
this is the 'rootfs' plugin but can be any of the more specialized
sources listed by the 'list source-plugins' command. Users can
also add their own source plugins - see 'wic help plugins' for
details.
"""
wic_ls_usage = """
List content of a partitioned image
usage: wic ls <image>[:<partition>[<path>]] [--native-sysroot <path>]
This command outputs either list of image partitions or directory contents
of vfat and ext* partitions.
See 'wic help ls' for more detailed instructions.
"""
wic_ls_help = """
NAME
wic ls - List contents of partitioned image or partition
SYNOPSIS
wic ls <image>
wic ls <image>:<vfat or ext* partition>
wic ls <image>:<vfat or ext* partition><path>
wic ls <image>:<vfat or ext* partition><path> --native-sysroot <path>
DESCRIPTION
This command lists either partitions of the image or directory contents
of vfat or ext* partitions.
The first form it lists partitions of the image.
For example:
$ wic ls tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic
Num Start End Size Fstype
1 1048576 24438783 23390208 fat16
2 25165824 50315263 25149440 ext4
Second and third form list directory content of the partition:
$ wic ls tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1
Volume in drive : is boot
Volume Serial Number is 2DF2-5F02
Directory for ::/
efi <DIR> 2017-05-11 10:54
startup nsh 26 2017-05-11 10:54
vmlinuz 6922288 2017-05-11 10:54
3 files 6 922 314 bytes
15 818 752 bytes free
$ wic ls tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1/EFI/boot/
Volume in drive : is boot
Volume Serial Number is 2DF2-5F02
Directory for ::/EFI/boot
. <DIR> 2017-05-11 10:54
.. <DIR> 2017-05-11 10:54
grub cfg 679 2017-05-11 10:54
bootx64 efi 571392 2017-05-11 10:54
4 files 572 071 bytes
15 818 752 bytes free
The -n option is used to specify the path to the native sysroot
containing the tools(parted and mtools) to use.
"""
wic_cp_usage = """
Copy files and directories to/from the vfat or ext* partition
usage: wic cp <src> <dest> [--native-sysroot <path>]
source/destination image in format <image>:<partition>[<path>]
This command copies files or directories either
- from local to vfat or ext* partitions of partitioned image
- from vfat or ext* partitions of partitioned image to local
See 'wic help cp' for more detailed instructions.
"""
wic_cp_help = """
NAME
wic cp - copy files and directories to/from the vfat or ext* partitions
SYNOPSIS
wic cp <src> <dest>:<partition>
wic cp <src>:<partition> <dest>
wic cp <src> <dest-image>:<partition><path>
wic cp <src> <dest-image>:<partition><path> --native-sysroot <path>
DESCRIPTION
This command copies files or directories either
- from local to vfat or ext* partitions of partitioned image
- from vfat or ext* partitions of partitioned image to local
The first form of it copies file or directory to the root directory of
the partition:
$ wic cp test.wks tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1
$ wic ls tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1
Volume in drive : is boot
Volume Serial Number is DB4C-FD4C
Directory for ::/
efi <DIR> 2017-05-24 18:15
loader <DIR> 2017-05-24 18:15
startup nsh 26 2017-05-24 18:15
vmlinuz 6926384 2017-05-24 18:15
test wks 628 2017-05-24 21:22
5 files 6 927 038 bytes
15 677 440 bytes free
The second form of the command copies file or directory to the specified directory
on the partition:
$ wic cp test tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1/efi/
$ wic ls tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1/efi/
Volume in drive : is boot
Volume Serial Number is DB4C-FD4C
Directory for ::/efi
. <DIR> 2017-05-24 18:15
.. <DIR> 2017-05-24 18:15
boot <DIR> 2017-05-24 18:15
test <DIR> 2017-05-24 21:27
4 files 0 bytes
15 675 392 bytes free
The third form of the command copies file or directory from the specified directory
on the partition to local:
$ wic cp tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1/vmlinuz test
The -n option is used to specify the path to the native sysroot
containing the tools(parted and mtools) to use.
"""
wic_rm_usage = """
Remove files or directories from the vfat or ext* partitions
usage: wic rm <image>:<partition><path> [--native-sysroot <path>]
This command removes files or directories from the vfat or ext* partitions of
the partitioned image.
See 'wic help rm' for more detailed instructions.
"""
wic_rm_help = """
NAME
wic rm - remove files or directories from the vfat or ext* partitions
SYNOPSIS
wic rm <src> <image>:<partition><path>
wic rm <src> <image>:<partition><path> --native-sysroot <path>
wic rm -r <image>:<partition><path>
DESCRIPTION
This command removes files or directories from the vfat or ext* partition of the
partitioned image:
$ wic ls ./tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1
Volume in drive : is boot
Volume Serial Number is 11D0-DE21
Directory for ::/
libcom32 c32 186500 2017-06-02 15:15
libutil c32 24148 2017-06-02 15:15
syslinux cfg 209 2017-06-02 15:15
vesamenu c32 27104 2017-06-02 15:15
vmlinuz 6926384 2017-06-02 15:15
5 files 7 164 345 bytes
16 582 656 bytes free
$ wic rm ./tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1/libutil.c32
$ wic ls ./tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic:1
Volume in drive : is boot
Volume Serial Number is 11D0-DE21
Directory for ::/
libcom32 c32 186500 2017-06-02 15:15
syslinux cfg 209 2017-06-02 15:15
vesamenu c32 27104 2017-06-02 15:15
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The -n option is used to specify the path to the native sysroot
containing the tools(parted and mtools) to use.
The -r option is used to remove directories and their contents
recursively,this only applies to ext* partition.
"""
wic_write_usage = """
Write image to a device
usage: wic write <image> <target device> [--expand [rules]] [--native-sysroot <path>]
This command writes partitioned image to a target device (USB stick, SD card etc).
See 'wic help write' for more detailed instructions.
"""
wic_write_help = """
NAME
wic write - write an image to a device
SYNOPSIS
wic write <image> <target>
wic write <image> <target> --expand auto
wic write <image> <target> --expand 1:100M,2:300M
wic write <image> <target> --native-sysroot <path>
DESCRIPTION
This command writes an image to a target device (USB stick, SD card etc)
$ wic write ./tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.wic /dev/sdb
The --expand option is used to resize image partitions.
--expand auto expands partitions to occupy all free space available on the target device.
It's also possible to specify expansion rules in a format
<partition>:<size>[,<partition>:<size>...] for one or more partitions.
Specifying size 0 will keep partition unmodified.
Note: Resizing boot partition can result in non-bootable image for non-EFI images. It is
recommended to use size 0 for boot partition to keep image bootable.
The --native-sysroot option is used to specify the path to the native sysroot
containing the tools(parted, resize2fs) to use.
"""
wic_plugins_help = """
NAME
wic plugins - Overview and API
DESCRIPTION
plugins allow wic functionality to be extended and specialized by
users. This section documents the plugin interface, which is
currently restricted to 'source' plugins.
'Source' plugins provide a mechanism to customize various aspects
of the image generation process in wic, mainly the contents of
partitions.
Source plugins provide a mechanism for mapping values specified in
.wks files using the --source keyword to a particular plugin
implementation that populates a corresponding partition.
A source plugin is created as a subclass of SourcePlugin (see
scripts/lib/wic/pluginbase.py) and the plugin file containing it
is added to scripts/lib/wic/plugins/source/ to make the plugin
implementation available to the wic implementation.
Source plugins can also be implemented and added by external
layers - any plugins found in a scripts/lib/wic/plugins/source/
or lib/wic/plugins/source/ directory in an external layer will
also be made available.
When the wic implementation needs to invoke a partition-specific
implementation, it looks for the plugin that has the same name as
the --source param given to that partition. For example, if the
partition is set up like this:
part /boot --source bootimg-pcbios ...
then the methods defined as class members of the plugin having the
matching bootimg-pcbios .name class member would be used.
To be more concrete, here's the plugin definition that would match
a '--source bootimg-pcbios' usage, along with an example method
that would be called by the wic implementation when it needed to
invoke an implementation-specific partition-preparation function:
class BootimgPcbiosPlugin(SourcePlugin):
name = 'bootimg-pcbios'
@classmethod
def do_prepare_partition(self, part, ...)
If the subclass itself doesn't implement a function, a 'default'
version in a superclass will be located and used, which is why all
plugins must be derived from SourcePlugin.
The SourcePlugin class defines the following methods, which is the
current set of methods that can be implemented/overridden by
--source plugins. Any methods not implemented by a SourcePlugin
subclass inherit the implementations present in the SourcePlugin
class (see the SourcePlugin source for details):
do_prepare_partition()
Called to do the actual content population for a
partition. In other words, it 'prepares' the final partition
image which will be incorporated into the disk image.
do_post_partition()
Called after the partition is created. It is useful to add post
operations e.g. signing the partition.
do_configure_partition()
Called before do_prepare_partition(), typically used to
create custom configuration files for a partition, for
example syslinux or grub config files.
do_install_disk()
Called after all partitions have been prepared and assembled
into a disk image. This provides a hook to allow
finalization of a disk image, for example to write an MBR to
it.
do_stage_partition()
Special content-staging hook called before
do_prepare_partition(), normally empty.
Typically, a partition will just use the passed-in
parameters, for example the unmodified value of bootimg_dir.
In some cases however, things may need to be more tailored.
As an example, certain files may additionally need to be
take from bootimg_dir + /boot. This hook allows those files
to be staged in a customized fashion. Note that
get_bitbake_var() allows you to access non-standard
variables that you might want to use for these types of
situations.
This scheme is extensible - adding more hooks is a simple matter
of adding more plugin methods to SourcePlugin and derived classes.
Please see the implementation for details.
"""
wic_overview_help = """
NAME
wic overview - General overview of wic
DESCRIPTION
The 'wic' command generates partitioned images from existing
OpenEmbedded build artifacts. Image generation is driven by
partitioning commands contained in an 'Openembedded kickstart'
(.wks) file (see 'wic help kickstart') specified either directly
on the command-line or as one of a selection of canned .wks files
(see 'wic list images'). When applied to a given set of build
artifacts, the result is an image or set of images that can be
directly written onto media and used on a particular system.
The 'wic' command and the infrastructure it's based on is by
definition incomplete - its purpose is to allow the generation of
customized images, and as such was designed to be completely
extensible via a plugin interface (see 'wic help plugins').
Background and Motivation
wic is meant to be a completely independent standalone utility
that initially provides easier-to-use and more flexible
replacements for a couple bits of existing functionality in
oe-core: directdisk.bbclass and mkefidisk.sh. The difference
between wic and those examples is that with wic the functionality
of those scripts is implemented by a general-purpose partitioning
'language' based on Red Hat kickstart syntax).
The initial motivation and design considerations that lead to the
current tool are described exhaustively in Yocto Bug #3847
(https://bugzilla.yoctoproject.org/show_bug.cgi?id=3847).
Implementation and Examples
wic can be used in two different modes, depending on how much
control the user needs in specifying the Openembedded build
artifacts that will be used in creating the image: 'raw' and
'cooked'.
If used in 'raw' mode, artifacts are explicitly specified via
command-line arguments (see example below).
The more easily usable 'cooked' mode uses the current MACHINE
setting and a specified image name to automatically locate the
artifacts used to create the image.
OE kickstart files (.wks) can of course be specified directly on
the command-line, but the user can also choose from a set of
'canned' .wks files available via the 'wic list images' command
(example below).
In any case, the prerequisite for generating any image is to have
the build artifacts already available. The below examples assume
the user has already build a 'core-image-minimal' for a specific
machine (future versions won't require this redundant step, but
for now that's typically how build artifacts get generated).
The other prerequisite is to source the build environment:
$ source oe-init-build-env
To start out with, we'll generate an image from one of the canned
.wks files. The following generates a list of availailable
images:
$ wic list images
mkefidisk Create an EFI disk image
directdisk Create a 'pcbios' direct disk image
You can get more information about any of the available images by
typing 'wic list xxx help', where 'xxx' is one of the image names:
$ wic list mkefidisk help
Creates a partitioned EFI disk image that the user can directly dd
to boot media.
At any time, you can get help on the 'wic' command or any
subcommand (currently 'list' and 'create'). For instance, to get
the description of 'wic create' command and its parameters:
$ wic create
Usage:
Create a new OpenEmbedded image
usage: wic create <wks file or image name> [-o <DIRNAME> | ...]
[-i <JSON PROPERTY FILE> | --infile <JSON PROPERTY_FILE>]
[-e | --image-name] [-s, --skip-build-check] [-D, --debug]
[-r, --rootfs-dir] [-b, --bootimg-dir] [-k, --kernel-dir]
[-n, --native-sysroot] [-f, --build-rootfs]
This command creates an OpenEmbedded image based on the 'OE
kickstart commands' found in the <wks file>.
The -o option can be used to place the image in a directory
with a different name and location.
See 'wic help create' for more detailed instructions.
...
As mentioned in the command, you can get even more detailed
information by adding 'help' to the above:
$ wic help create
So, the easiest way to create an image is to use the -e option
with a canned .wks file. To use the -e option, you need to
specify the image used to generate the artifacts and you actually
need to have the MACHINE used to build them specified in your
local.conf (these requirements aren't necessary if you aren't
using the -e options.) Below, we generate a directdisk image,
pointing the process at the core-image-minimal artifacts for the
current MACHINE:
$ wic create directdisk -e core-image-minimal
Checking basic build environment...
Done.
Creating image(s)...
Info: The new image(s) can be found here:
/var/tmp/wic/build/directdisk-201309252350-sda.direct
The following build artifacts were used to create the image(s):
ROOTFS_DIR: ...
BOOTIMG_DIR: ...
KERNEL_DIR: ...
NATIVE_SYSROOT: ...
The image(s) were created using OE kickstart file:
.../scripts/lib/wic/canned-wks/directdisk.wks
The output shows the name and location of the image created, and
so that you know exactly what was used to generate the image, each
of the artifacts and the kickstart file used.
Similarly, you can create a 'mkefidisk' image in the same way
(notice that this example uses a different machine - because it's
using the -e option, you need to change the MACHINE in your
local.conf):
$ wic create mkefidisk -e core-image-minimal
Checking basic build environment...
Done.
Creating image(s)...
Info: The new image(s) can be found here:
/var/tmp/wic/build/mkefidisk-201309260027-sda.direct
...
Here's an example that doesn't take the easy way out and manually
specifies each build artifact, along with a non-canned .wks file,
and also uses the -o option to have wic create the output
somewhere other than the default /var/tmp/wic:
$ wic create ./test.wks -o ./out --rootfs-dir
tmp/work/qemux86_64-poky-linux/core-image-minimal/1.0-r0/rootfs
--bootimg-dir tmp/sysroots/qemux86-64/usr/share
--kernel-dir tmp/deploy/images/qemux86-64
--native-sysroot tmp/sysroots/x86_64-linux
Creating image(s)...
Info: The new image(s) can be found here:
out/build/test-201507211313-sda.direct
The following build artifacts were used to create the image(s):
ROOTFS_DIR: tmp/work/qemux86_64-poky-linux/core-image-minimal/1.0-r0/rootfs
BOOTIMG_DIR: tmp/sysroots/qemux86-64/usr/share
KERNEL_DIR: tmp/deploy/images/qemux86-64
NATIVE_SYSROOT: tmp/sysroots/x86_64-linux
The image(s) were created using OE kickstart file:
./test.wks
Here is a content of test.wks:
part /boot --source bootimg-pcbios --ondisk sda --label boot --active --align 1024
part / --source rootfs --ondisk sda --fstype=ext3 --label platform --align 1024
bootloader --timeout=0 --append="rootwait rootfstype=ext3 video=vesafb vga=0x318 console=tty0"
Finally, here's an example of the actual partition language
commands used to generate the mkefidisk image i.e. these are the
contents of the mkefidisk.wks OE kickstart file:
# short-description: Create an EFI disk image
# long-description: Creates a partitioned EFI disk image that the user
# can directly dd to boot media.
part /boot --source bootimg-efi --ondisk sda --fstype=efi --active
part / --source rootfs --ondisk sda --fstype=ext3 --label platform
part swap --ondisk sda --size 44 --label swap1 --fstype=swap
bootloader --timeout=10 --append="rootwait console=ttyPCH0,115200"
You can get a complete listing and description of all the
kickstart commands available for use in .wks files from 'wic help
kickstart'.
"""
wic_kickstart_help = """
NAME
wic kickstart - wic kickstart reference
DESCRIPTION
This section provides the definitive reference to the wic
kickstart language. It also provides documentation on the list of
--source plugins available for use from the 'part' command (see
the 'Platform-specific Plugins' section below).
The current wic implementation supports only the basic kickstart
partitioning commands: partition (or part for short) and
bootloader.
The following is a listing of the commands, their syntax, and
meanings. The commands are based on the Fedora kickstart
documentation but with modifications to reflect wic capabilities.
https://pykickstart.readthedocs.io/en/latest/kickstart-docs.html#part-or-partition
https://pykickstart.readthedocs.io/en/latest/kickstart-docs.html#bootloader
Commands
* 'part' or 'partition'
This command creates a partition on the system and uses the
following syntax:
part [<mountpoint>]
The <mountpoint> is where the partition will be mounted and
must take of one of the following forms:
/<path>: For example: /, /usr, or /home
swap: The partition will be used as swap space.
If a <mountpoint> is not specified the partition will be created
but will not be mounted.
Partitions with a <mountpoint> specified will be automatically mounted.
This is achieved by wic adding entries to the fstab during image
generation. In order for a valid fstab to be generated one of the
--ondrive, --ondisk, --use-uuid or --use-label partition options must
be used for each partition that specifies a mountpoint. Note that with
--use-{uuid,label} and non-root <mountpoint>, including swap, the mount
program must understand the PARTUUID or LABEL syntax. This currently
excludes the busybox versions of these applications.
The following are supported 'part' options:
--size: The minimum partition size. Specify an integer value
such as 500. Multipliers k, M ang G can be used. If
not specified, the size is in MB.
You do not need this option if you use --source.
--fixed-size: Exact partition size. Value format is the same
as for --size option. This option cannot be
specified along with --size. If partition data
is larger than --fixed-size and error will be
raised when assembling disk image.
--source: This option is a wic-specific option that names the
source of the data that will populate the
partition. The most common value for this option
is 'rootfs', but can be any value which maps to a
valid 'source plugin' (see 'wic help plugins').
If '--source rootfs' is used, it tells the wic
command to create a partition as large as needed
and to fill it with the contents of the root
filesystem pointed to by the '-r' wic command-line
option (or the equivalent rootfs derived from the
'-e' command-line option). The filesystem type
that will be used to create the partition is driven
by the value of the --fstype option specified for
the partition (see --fstype below).
If --source <plugin-name>' is used, it tells the
wic command to create a partition as large as
needed and to fill with the contents of the
partition that will be generated by the specified
plugin name using the data pointed to by the '-r'
wic command-line option (or the equivalent rootfs
derived from the '-e' command-line option).
Exactly what those contents and filesystem type end
up being are dependent on the given plugin
implementation.
If --source option is not used, the wic command
will create empty partition. --size parameter has
to be used to specify size of empty partition.
--ondisk or --ondrive: Forces the partition to be created on
a particular disk.
--fstype: Sets the file system type for the partition. These
apply to partitions created using '--source rootfs' (see
--source above). Valid values are:
vfat
msdos
ext2
ext3
ext4
btrfs
squashfs
erofs
swap
--fsoptions: Specifies a free-form string of options to be
used when mounting the filesystem. This string
will be copied into the /etc/fstab file of the
installed system and should be enclosed in
quotes. If not specified, the default string is
"defaults".
--fspassno: Specifies the order in which filesystem checks are done
at boot time by fsck. See fs_passno parameter of
fstab(5). This parameter will be copied into the
/etc/fstab file of the installed system. If not
specified the default value of "0" will be used.
--label label: Specifies the label to give to the filesystem
to be made on the partition. If the given
label is already in use by another filesystem,
a new label is created for the partition.
--use-label: This option is specific to wic. It makes wic to use the
label in /etc/fstab to specify a partition. If the
--use-label and --use-uuid are used at the same time,
we prefer the uuid because it is less likely to cause
name confliction. We don't support using this parameter
on the root partition since it requires an initramfs to
parse this value and we do not currently support that.
--active: Marks the partition as active.
--align (in KBytes): This option is specific to wic and says
to start a partition on an x KBytes
boundary.
--no-table: This option is specific to wic. Space will be
reserved for the partition and it will be
populated but it will not be added to the
partition table. It may be useful for
bootloaders.
--exclude-path: This option is specific to wic. It excludes the given
relative path from the resulting image. If the path
ends with a slash, only the content of the directory
is omitted, not the directory itself. This option only
has an effect with the rootfs source plugin.
--include-path: This option is specific to wic. It adds the contents
of the given path or a rootfs to the resulting image.
The option contains two fields, the origin and the
destination. When the origin is a rootfs, it follows
the same logic as the rootfs-dir argument and the
permissions and owners are kept. When the origin is a
path, it is relative to the directory in which wic is
running not the rootfs itself so use of an absolute
path is recommended, and the owner and group is set to
root:root. If no destination is given it is
automatically set to the root of the rootfs. This
option only has an effect with the rootfs source
plugin.
--change-directory: This option is specific to wic. It changes to the
given directory before copying the files. This
option is useful when we want to split a rootfs in
multiple partitions and we want to keep the right
permissions and usernames in all the partitions.
--no-fstab-update: This option is specific to wic. It does not update the
'/etc/fstab' stock file for the given partition.
--extra-space: This option is specific to wic. It adds extra
space after the space filled by the content
of the partition. The final size can go
beyond the size specified by --size.
By default, 10MB. This option cannot be used
with --fixed-size option.
--overhead-factor: This option is specific to wic. The
size of the partition is multiplied by
this factor. It has to be greater than or
equal to 1. The default value is 1.3.
This option cannot be used with --fixed-size
option.
--part-name: This option is specific to wic. It specifies name for GPT partitions.
--part-type: This option is specific to wic. It specifies partition
type GUID for GPT partitions.
List of partition type GUIDS can be found here:
http://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_type_GUIDs
--use-uuid: This option is specific to wic. It makes wic to generate
random globally unique identifier (GUID) for the partition
and use it in bootloader configuration to specify root partition.
--uuid: This option is specific to wic. It specifies partition UUID.
It's useful if preconfigured partition UUID is added to kernel command line
in bootloader configuration before running wic. In this case .wks file can
be generated or modified to set preconfigured parition UUID using this option.
--fsuuid: This option is specific to wic. It specifies filesystem UUID.
It's useful if preconfigured filesystem UUID is added to kernel command line
in bootloader configuration before running wic. In this case .wks file can
be generated or modified to set preconfigured filesystem UUID using this option.
--system-id: This option is specific to wic. It specifies partition system id. It's useful
for the harware that requires non-default partition system ids. The parameter
in one byte long hex number either with 0x prefix or without it.
--mkfs-extraopts: This option specifies extra options to pass to mkfs utility.
NOTE, that wic uses default options for some filesystems, for example
'-S 512' for mkfs.fat or '-F -i 8192' for mkfs.ext. Those options will
not take effect when --mkfs-extraopts is used. This should be taken into
account when using --mkfs-extraopts.
* bootloader
This command allows the user to specify various bootloader
options. The following are supported 'bootloader' options:
--timeout: Specifies the number of seconds before the
bootloader times out and boots the default option.
--append: Specifies kernel parameters. These will be added to
bootloader command-line - for example, the syslinux
APPEND or grub kernel command line.
--configfile: Specifies a user defined configuration file for
the bootloader. This file must be located in the
canned-wks folder or could be the full path to the
file. Using this option will override any other
bootloader option.
Note that bootloader functionality and boot partitions are
implemented by the various --source plugins that implement
bootloader functionality; the bootloader command essentially
provides a means of modifying bootloader configuration.
* include
This command allows the user to include the content of .wks file
into original .wks file.
Command uses the following syntax:
include <file>
The <file> is either path to the file or its name. If name is
specified wic will try to find file in the directories with canned
.wks files.
"""
wic_help_help = """
NAME
wic help - display a help topic
DESCRIPTION
Specify a help topic to display it. Topics are shown above.
"""
wic_help = """
Creates a customized OpenEmbedded image.
Usage: wic [--version]
wic help [COMMAND or TOPIC]
wic COMMAND [ARGS]
usage 1: Returns the current version of Wic
usage 2: Returns detailed help for a COMMAND or TOPIC
usage 3: Executes COMMAND
COMMAND:
list - List available canned images and source plugins
ls - List contents of partitioned image or partition
rm - Remove files or directories from the vfat or ext* partitions
help - Show help for a wic COMMAND or TOPIC
write - Write an image to a device
cp - Copy files and directories to the vfat or ext* partitions
create - Create a new OpenEmbedded image
TOPIC:
overview - Presents an overall overview of Wic
plugins - Presents an overview and API for Wic plugins
kickstart - Presents a Wic kickstart file reference
Examples:
$ wic --version
Returns the current version of Wic
$ wic help cp
Returns the SYNOPSIS and DESCRIPTION for the Wic "cp" command.
$ wic list images
Returns the list of canned images (i.e. *.wks files located in
the /scripts/lib/wic/canned-wks directory.
$ wic create mkefidisk -e core-image-minimal
Creates an EFI disk image from artifacts used in a previous
core-image-minimal build in standard BitBake locations
(e.g. Cooked Mode).
"""
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