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diff --git a/documentation/sdk-manual/sdk-appendix-customizing.xml b/documentation/sdk-manual/sdk-appendix-customizing.xml index 2068143df3..3ee0d7c90a 100644 --- a/documentation/sdk-manual/sdk-appendix-customizing.xml +++ b/documentation/sdk-manual/sdk-appendix-customizing.xml @@ -6,17 +6,380 @@ <title>Customizing the SDK</title> -<para role='writernotes'> - This chapter is going to cover the details on extending the SDK through - user customizations. - I am not sure if this is possible for both the standard and extensible - SDK or what. +<para> + This appendix presents customizations you can apply to both the standard + and extensible SDK. + Each subsection identifies the type of SDK to which the section applies. </para> -<para role='writernotes'> - I do not have a feel for what sub-topics need to be covered here. - I need to get this information from Paul. -</para> +<section id='sdk-configuring-the-extensible-sdk'> + <title>Configuring the Extensible SDK</title> + + <para> + The extensible SDK primarily consists of a pre-configured copy of + the build system from which it was produced. + Thus, the SDK's configuration is derived using that build system. + However, filters exist that are applied such as the following that + are applied to <filename>local.conf</filename> and + <filename>auto.conf</filename> when present: + <itemizedlist> + <listitem><para> + Variables whose values start with "/" are excluded since the + assumption is that those values are paths that are likely to + be specific to the build host. + </para></listitem> + <listitem><para> + Variables listed in + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_LOCAL_CONF_BLACKLIST'><filename>SDK_LOCAL_CONF_BLACKLIST</filename></ulink> + are excluded. + The default value blacklists + <ulink url='&YOCTO_DOCS_REF_URL;#var-CONF_VERSION'><filename>CONF_VERSION</filename></ulink>, + <ulink url='&YOCTO_DOCS_REF_URL;#var-BB_NUMBER_THREADS'><filename>BB_NUMBER_THREADS</filename></ulink>, + <ulink url='&YOCTO_DOCS_REF_URL;#var-PARALLEL_MAKE'><filename>PARALLEL_MAKE</filename></ulink>, + <ulink url='&YOCTO_DOCS_REF_URL;#var-PRSERV_HOST'><filename>PRSERV_HOST</filename></ulink>, + and + <ulink url='&YOCTO_DOCS_REF_URL;#var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></ulink>. + </para></listitem> + <listitem><para> + Variables listed in + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_LOCAL_CONF_WHITELIST'><filename>SDK_LOCAL_CONF_WHITELIST</filename></ulink> + are included. + Including these variables overrides either of the above two + conditions. + The default value is blank. + </para></listitem> + <listitem><para> + Classes inherited globally with + <ulink url='&YOCTO_DOCS_REF_URL;#var-INHERIT'><filename>INHERIT</filename></ulink> + that are listed in + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INHERIT_BLACKLIST'><filename>SDK_INHERIT_BLACKLIST</filename></ulink> + are disabled. + Using <filename>SDK_INHERIT_BLACKLIST</filename> to disable + these classes is is the typical method to disable classes that + are problematic or unnecessary in the SDK context. + The default value blacklists the + <ulink url='&YOCTO_DOCS_REF_URL;#ref-classes-buildhistory'><filename>buildhistory</filename></ulink> + and + <ulink url='&YOCTO_DOCS_REF_URL;#ref-classes-icecc'><filename>icecc</filename></ulink> + classes. + </para></listitem> + </itemizedlist> + Additionally, the contents of <filename>conf/sdk-extra.conf</filename>, + when present, are appended to the end of + <filename>conf/local.conf</filename> within the produced SDK, without + any filtering. + Not filtering these contents is particularly useful if you want to + set a variable value just for the SDK and not the build system used to + create the SDK. + </para> +</section> + +<section id='adjusting-the-extensible-sdk-to-suit-your-build-system-setup'> + <title>Adjusting the Extensible SDK to Suit Your Build System Setup</title> + + <para> + In most cases, the extensible SDK defaults should work. + However, some cases exist for which you might consider making + adjustments: + <itemizedlist> + <listitem><para> + If your SDK configuration inherits additional classes + using the + <ulink url='&YOCTO_DOCS_REF_URL;#var-INHERIT'><filename>INHERIT</filename></ulink> + variable and you do not need or want those classes enabled in + the SDK, you can blacklist them by adding them to the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INHERIT_BLACKLIST'><filename>SDK_INHERIT_BLACKLIST</filename></ulink> + variable. + The default value of <filename>SDK_INHERIT_BLACKLIST</filename> + is set using the "?=" operator. + Consequently, you will need to either set the complete value + using "=" or append the value using "_append". + </para></listitem> + <listitem><para> + If you have classes or recipes that add additional tasks to + the standard build flow (i.e. that execute as part of building + the recipe as opposed to needing to be called explicitly), then + you need to do one of the following: + <itemizedlist> + <listitem><para> + Ensure the tasks are shared state tasks (i.e. their + output is saved to and can be restored from the shared + state cache), or that the tasks are able to be + produced quickly from a task that is a shared state + task and add the task name to the value of + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_RECRDEP_TASKS'><filename>SDK_RECRDEP_TASKS</filename></ulink>. + </para></listitem> + <listitem><para> + Disable the tasks if they are added by a class and + you do not need the functionality the class provides + in the extensible SDK. + To disable the tasks, add the class to + <filename>SDK_INHERIT_BLACKLIST</filename> as previously + described. + </para></listitem> + </itemizedlist> + </para></listitem> + <listitem><para> + Generally, you want to have a shared state mirror set up so + users of the SDK can add additional items to the SDK after + installation without needing to build the items from source. + See the + "<link linkend='sdk-providing-additional-installable-extensible-sdk-content'>Providing Additional Installable Extensible SDK Content</link>" + section for information. + </para></listitem> + <listitem><para> + If you want users of the SDK to be able to easily update the + SDK, you need to set the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_UPDATE_URL'><filename>SDK_UPDATE_URL</filename></ulink> + variable. + For more information, see the + "<link linkend='sdk-providing-updates-after-installing-the-extensible-sdk'>Providing Updates After Installing the Extensible SDK</link>" + section. + </para></listitem> + <listitem><para> + If you have adjusted the list of files and directories that + appear in + <ulink url='&YOCTO_DOCS_REF_URL;#var-COREBASE'><filename>COREBASE</filename></ulink> + (other than layers that are enabled through + <filename>bblayers.conf</filename>), then must list these + files in + <ulink url='&YOCTO_DOCS_REF_URL;#var-COREBASE_FILES'><filename>COREBASE_FILES</filename></ulink> + so that the files are copied into the SDK. + </para></listitem> + <listitem><para> + If your build system setup uses a different environment setup + script other than + <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>&OE_INIT_FILE;</filename></ulink> + or + <ulink url='&YOCTO_DOCS_REF_URL;#structure-memres-core-script'><filename>oe-init-build-env-memres</filename></ulink>, + then you must set + <ulink url='&YOCTO_DOCS_REF_URL;#var-OE_INIT_ENV_SCRIPT'><filename>OE_INIT_ENV_SCRIPT</filename></ulink> + to point to the environment setup script you use. + <note> + You must also reflect this change in the value used for the + <filename>COREBASE_FILES</filename> variable as previously + described. + </note> + </para></listitem> + </itemizedlist> + </para> +</section> + +<section id='sdk-changing-the-appearance-of-the-extensible-sdk'> + <title>Changing the Appearance of the Extensible SDK</title> + + <para> + You can change the title shown by the SDK installer by setting the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_TITLE'><filename>SDK_TITLE</filename></ulink> + variable. + By default, this title is derived from + <ulink url='&YOCTO_DOCS_REF_URL;#var-DISTRO_NAME'><filename>DISTRO_NAME</filename></ulink> + when it is set. + If the <filename>DISTRO_NAME</filename> variable is not set, the title + is derived from the + <ulink url='&YOCTO_DOCS_REF_URL;#var-DISTRO'><filename>DISTRO</filename></ulink> + variable. + </para> +</section> + +<section id='sdk-providing-updates-after-installing-the-extensible-sdk'> + <title>Providing Updates After Installing the Extensible SDK</title> + + <para> + When you make changes to your configuration or to the metadata and + if you want those changes to be reflected in installed SDKs, you need + to perform additional steps to make it possible for those that use + the SDK to update their installations with the + <filename>devtool sdk-update</filename> command: + <orderedlist> + <listitem><para> + Arrange to be created a directory that can be shared over + HTTP or HTTPS. + </para></listitem> + <listitem><para> + Set the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_UPDATE_URL'><filename>SDK_UPDATE_URL</filename></ulink> + variable to point to the corresponding HTTP or HTTPS URL. + Setting this variable causes any SDK built to default to that + URL and thus, the user does not have to pass the URL to the + <filename>devtool sdk-update</filename> command. + </para></listitem> + <listitem><para> + Build the extensible SDK normally (i.e., use the + <filename>bitbake -c populate_sdk_ext</filename> <replaceable>imagename</replaceable> + command). + </para></listitem> + <listitem><para> + Publish the SDK using the following command: + <literallayout class='monospaced'> + $ oe-publish-sdk <replaceable>some_path</replaceable>/sdk-installer.sh <replaceable>path_to_shared/http_directory</replaceable> + </literallayout> + You must repeat this step each time you rebuild the SDK + with changes that you want to make available through the + update mechanism. + </para></listitem> + </orderedlist> + </para> + + <para> + Completing the above steps allows users of the existing SDKs to + simply run <filename>devtool sdk-update</filename> to retrieve the + latest updates. + See the + "<link linkend='sdk-updating-the-extensible-sdk'>Updating the Extensible SDK</link>" + section for further information. + </para> +</section> + +<section id='sdk-providing-additional-installable-extensible-sdk-content'> + <title>Providing Additional Installable Extensible SDK Content</title> + + <para> + If you want the users of the extensible SDK you are building to be + able to add items to the SDK without needing to build the + items from source, you need to do a number of things: + <orderedlist> + <listitem><para> + Ensure the additional items you want the user to be able to + install are actually built. + You can ensure these items are built a number of different + ways: 1) Build them explicitly, perhaps using one or more + "meta" recipes that depend on lists of other recipes to keep + things tidy, or 2) Build the "world" target and set + <filename>EXCLUDE_FROM_WORLD_pn-</filename><replaceable>recipename</replaceable> + for the recipes you do not want built. + See the + <ulink url='&YOCTO_DOCS_REF_URL;#var-EXCLUDE_FROM_WORLD'><filename>EXCLUDE_FROM_WORLD</filename></ulink> + variable for additional information. + </para></listitem> + <listitem><para> + Expose the <filename>sstate-cache</filename> directory + produced by the build. + Typically, you expose this directory over HTTP or HTTPS. + </para></listitem> + <listitem><para> + Set the appropriate configuration so that the produced SDK + knows how to find the configuration. + The variable you need to set is + <ulink url='&YOCTO_DOCS_REF_URL;#var-SSTATE_MIRRORS'><filename>SSTATE_MIRRORS</filename></ulink>: + <literallayout class='monospaced'> + SSTATE_MIRRORS = "file://.* http://<replaceable>example</replaceable>.com/<replaceable>some_path</replaceable>/sstate-cache/PATH" + </literallayout> + You can set the <filename>SSTATE_MIRRORS</filename> variable + in two different places: + <itemizedlist> + <listitem><para> + If the mirror value you are setting is appropriate to + be set for both the build system that is actually + building the SDK and the SDK itself (i.e. the mirror + is accessible in both places or it will fail quickly + on the build system side, and its contents will not + interfere with the build), then you can set the + variable in your <filename>local.conf</filename> + or custom distro configuration file. + You can "whitelist" the variable through the SDK by + adding the following: + <literallayout class='monospaced'> + SDK_LOCAL_CONF_WHITELIST = "SSTATE_MIRRORS" + </literallayout> + </para></listitem> + <listitem><para> + Alternatively, if you just want to set the + <filename>SSTATE_MIRRORS</filename> variable's value + for the SDK alone, create a + <filename>conf/sdk-extra.conf</filename> either in + your + <ulink url='&YOCTO_DOCS_DEV_URL;#build-directory'>Build Directory</ulink> + or within any layer and put your + <filename>SSTATE_MIRRORS</filename> setting within + that file. + <note> + This second option is the safest option should + you have any doubts as to which method to use when + setting <filename>SSTATE_MIRRORS</filename>. + </note> + </para></listitem> + </itemizedlist> + </para></listitem> + </orderedlist> + </para> +</section> + +<section id='sdk-minimizing-the-size-of-the-extensible-sdk-installer-download'> + <title>Minimizing the Size of the Extensible SDK Installer Download</title> + + <para> + By default, the extensible SDK bundles the shared state artifacts for + everything needed to reconstruct the image for which the SDK was built. + This bundling can lead to an SDK installer file that is a Gigabyte or + more in size. + If the size of this file causes a problem, you can build an SDK that + has just enough in it to install and provide access to the + <filename>devtool command</filename> by setting the following in your + configuration: + <literallayout class='monospaced'> + SDK_EXT_TYPE = "minimal" + </literallayout> + Setting + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_EXT_TYPE'><filename>SDK_EXT_TYPE</filename></ulink> + to "minimal" produces an SDK installer that is around 35 Mbytes in + size, which downloads and installs quickly. + You need to realize, though, that the installer does not install any + libraries or tools out of the box. + These must be installed either "on the fly" or through actions you + perform using <filename>devtool</filename> or explicitly with the + <filename>devtool sdk-install</filename> command. + </para> + + <para> + In most cases, when building a minimal SDK you will need to also enable + bringing in the information on a wider range of packages produced by + the system. + This is particularly true so that <filename>devtool add</filename> + is able to effectively map dependencies it discovers in a source tree + to the appropriate recipes. + Also so that the <filename>devtool search</filename> command + is able to return useful results. + </para> + + <para> + To facilitate this wider range of information, you would additionally + set the following: + <literallayout class='monospaced'> + SDK_INCLUDE_PKGDATA = "1" + </literallayout> + See the + <ulink url='&YOCTO_DOCS_REF_URL;#var-SDK_INCLUDE_PKGDATA'><filename>SDK_INCLUDE_PKGDATA</filename></ulink> + variable for additional information. + </para> + + <para> + Setting the <filename>SDK_INCLUDE_PKGDATA</filename> variable as + shown causes the "world" target to be built so that information + for all of the recipes included within it are available. + Having these recipes available increases build time significantly and + increases the size of the SDK installer by 30-80 Mbytes depending on + how many recipes are included in your configuration. + </para> + + <para> + You can use + <filename>EXCLUDE_FROM_WORLD_pn-</filename><replaceable>recipename</replaceable> + for recipes you want to exclude. + However, it is assumed that you would need to be building the "world" + target if you want to provide additional items to the SDK. + Consequently, building for "world" should not represent undue + overhead in most cases. + <note> + If you set <filename>SDK_EXT_TYPE</filename> to "minimal", + then providing a shared state mirror is mandatory so that items + can be installed as needed. + See the + "<link linkend='sdk-providing-additional-installable-extensible-sdk-content'>Providing Additional Installable Extensible SDK Content</link>" + section for more information. + </note> + </para> +</section> </appendix> <!-- |