# ex:ts=4:sw=4:sts=4:et # -*- tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- # # Copyright (c) 2013, Intel Corporation. # All rights reserved. # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License version 2 as # published by the Free Software Foundation. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License along # with this program; if not, write to the Free Software Foundation, Inc., # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. # # 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 # import subprocess import logging from wic.plugin import pluginmgr, PLUGIN_TYPES def subcommand_error(args): logging.info("invalid subcommand %s" % args[0]) def display_help(subcommand, subcommands): """ Display help for subcommand. """ if subcommand not in subcommands: return False help = subcommands.get(subcommand, subcommand_error)[2] pager = subprocess.Popen('less', stdin=subprocess.PIPE) pager.communicate(help) return True def wic_help(args, usage_str, subcommands): """ Subcommand help dispatcher. """ if len(args) == 1 or not display_help(args[1], 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).iteritems(): 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: logging.error("No subcommand specified, exiting") parser.print_help() elif args[0] == "help": wic_help(args, main_command_usage, subcommands) elif args[0] not in subcommands: logging.error("Unsupported subcommand %s, exiting\n" % (args[0])) parser.print_help() else: usage = subcommands.get(args[0], subcommand_error)[1] subcommands.get(args[0], subcommand_error)[0](args[1:], usage) ## # wic help and usage strings ## wic_usage = """ Create a customized OpenEmbedded image usage: wic [--version] [--help] COMMAND [ARGS] Current 'wic' commands are: create Create a new OpenEmbedded image list List available values for options and image properties Help topics: overview wic overview - General overview of wic plugins wic plugins - Overview and API kickstart wic kickstart - wic kickstart reference See 'wic help ' for more information on a specific command or help topic. """ wic_help_usage = """ usage: wic help This command displays detailed help for the specified subcommand. """ wic_create_usage = """ Create a new OpenEmbedded image usage: wic create [-o | --outdir ] [-i | --infile ] [-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 . 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 [-o | --outdir ] [-i | --infile ] [-e | --image-name] [-s, --skip-build-check] [-D, --debug] [-r, --rootfs-dir] [-b, --bootimg-dir] [-k, --kernel-dir] [-n, --native-sysroot] [-f, --build-rootfs] DESCRIPTION This command creates an OpenEmbedded image based on the 'OE kickstart commands' found in the . 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 " 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. As an alternative to the wks file, the image-specific properties that define the values that will be used to generate a particular image can be specified on the command-line using the -i option and supplying a JSON object consisting of the set of name:value pairs needed by image creation. The set of properties available for a given image type can be listed using the 'wic list' command. """ wic_list_usage = """ List available OpenEmbedded image properties and values usage: wic list images wic list help wic list source-plugins wic list properties wic list properties wic list property [-o | --outfile ] This command enumerates the set of available canned images as well as help for those images. It also can be used to enumerate the complete set of possible values for a specified option or property needed by the image creation process. 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). The fourth form enumerates all the possible values that exist and can be specified in an OE kickstart (wks) file. The fifth form enumerates all the possible options that exist for the set of properties specified in a given OE kickstart (ks) file. The final form enumerates all the possible values that exist and can be specified for any given OE kickstart (wks) property. See 'wic help list' for more details. """ wic_list_help = """ NAME wic list - List available OpenEmbedded image properties and values SYNOPSIS wic list images wic list help wic list source-plugins wic list properties wic list properties wic list property [-o | --outfile ] DESCRIPTION This command enumerates the complete set of possible values for a specified option or property needed by the image creation process. This command enumerates the set of available canned images as well as help for those images. It also can be used to enumerate the complete set of possible values for a specified option or property needed by the image creation process. 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/image/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. The third form enumerates all the possible values that exist and can be specified in a OE kickstart (wks) file. The output of this can be used by the third form to print the description and possible values of a specific property. The fourth form enumerates all the possible options that exist for the set of properties specified in a given OE kickstart (wks) file. If the -o option is specified, the list of properties, in addition to being displayed, will be written to the specified file as a JSON object. In this case, the object will consist of the set of name:value pairs corresponding to the (possibly nested) dictionary of properties defined by the input statements used by the image. Some example output for the 'list ' command: $ wic list test.ks "part" : { "mountpoint" : "/" "fstype" : "ext3" } "part" : { "mountpoint" : "/home" "fstype" : "ext3" "offset" : "10000" } "bootloader" : { "type" : "efi" } . . . Each entry in the output consists of the name of the input element e.g. "part", followed by the properties defined for that element enclosed in braces. This information should provide sufficient information to create a complete user interface with. The final form enumerates all the possible values that exist and can be specified for any given OE kickstart (wks) property. If the -o option is specified, the list of values for the given property, in addition to being displayed, will be written to the specified file as a JSON object. In this case, the object will consist of the set of name:value pairs corresponding to the array of property values associated with the property. $ wic list property part ["mountpoint", "where the partition should be mounted"] ["fstype", "filesytem type of the partition"] ["ext3"] ["ext4"] ["btrfs"] ["swap"] ["offset", "offset of the partition within the image"] """ 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/ 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_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. The code that then needs to call the plugin methods uses plugin.get_source_plugin_methods() to find the method(s) needed by the call; this is done by filling up a dict with keys containing the method names of interest - on success, these will be filled in with the actual methods. Please see the implementation for examples and 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 Redhat 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 [-o | ...] [-i | --infile ] [-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 . 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/image/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 /home/trz/testwic --rootfs-dir /home/trz/yocto/build/tmp/work/crownbay/core-image-minimal/1.0-r0/rootfs --bootimg-dir /home/trz/yocto/build/tmp/sysroots/crownbay/usr/share --kernel-dir /home/trz/yocto/build/tmp/sysroots/crownbay/usr/src/kernel --native-sysroot /home/trz/yocto/build/tmp/sysroots/x86_64-linux Creating image(s)... Info: The new image(s) can be found here: /home/trz/testwic/build/test-201309260032-sda.direct ... 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. http://fedoraproject.org/wiki/Anaconda/Kickstart#part_or_partition http://fedoraproject.org/wiki/Anaconda/Kickstart#bootloader Commands * 'part' or 'partition' This command creates a partition on the system and uses the following syntax: part The is where the partition will be mounted and must take of one of the following forms: /: For example: /, /usr, or /home swap: The partition will be used as swap space. 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. --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 ' 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: ext2 ext3 ext4 btrfs squashfs 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". --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. --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. --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. --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. --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. * 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. 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. """