docs/manual/legal-notice.txt - buildroot - Git at Google

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 [[legal-info]]

 == Legal notice and licensing

 === Complying with open source licenses

 All of the end products of Buildroot (toolchain, root filesystem, kernel,
 bootloaders) contain open source software, released under various licenses.

 Using open source software gives you the freedom to build rich embedded
 systems, choosing from a wide range of packages, but also imposes some
 obligations that you must know and honour.
 Some licenses require you to publish the license text in the documentation of
 your product. Others require you to redistribute the source code of the
 software to those that receive your product.

 The exact requirements of each license are documented in each package, and
 it is your responsibility (or that of your legal office) to comply with those
 requirements.
 To make this easier for you, Buildroot can collect for you some material you
 will probably need. To produce this material, after you have configured
 Buildroot with +make menuconfig+, +make xconfig+ or +make gconfig+, run:

 --------------------
 make legal-info
 --------------------

 Buildroot will collect legally-relevant material in your output directory,
 under the +legal-info/+ subdirectory.
 There you will find:

 * A +README+ file, that summarizes the produced material and contains warnings
   about material that Buildroot could not produce.
 * +buildroot.config+: this is the Buildroot configuration file that is usually
   produced with +make menuconfig+, and which is necessary to reproduce the
   build.
 * The source code for all packages; this is saved in the +sources/+ and
   +host-sources/+ subdirectories for target and host packages respectively.
   The source code for packages that set +<PKG>_REDISTRIBUTE = NO+ will not be
   saved.
   Patches that were applied are also saved, along with a file named +series+
   that lists the patches in the order they were applied. Patches are under the
   same license as the files that they modify.
   Note: Buildroot applies additional patches to Libtool scripts of
   autotools-based packages. These patches can be found under
   +support/libtool+ in the Buildroot source and, due to technical
   limitations, are not saved with the package sources. You may need to
   collect them manually.
 * A manifest file (one for host and one for target packages) listing the
   configured packages, their version, license and related information.
   Some of this information might not be defined in Buildroot; such items are
   marked as "unknown".
 * The license texts of all packages, in the +licenses/+ and +host-licenses/+
   subdirectories for target and host packages respectively.
   If the license file(s) are not defined in Buildroot, the file is not produced
   and a warning in the +README+ indicates this.

 Please note that the aim of the +legal-info+ feature of Buildroot is to
 produce all the material that is somehow relevant for legal compliance with the
 package licenses. Buildroot does not try to produce the exact material that
 you must somehow make public. Certainly, more material is produced than is
 needed for a strict legal compliance. For example, it produces the source code
 for packages released under BSD-like licenses, that you are not required to
 redistribute in source form.

 Moreover, due to technical limitations, Buildroot does not produce some
 material that you will or may need, such as the toolchain source code and the
 Buildroot source code itself (including patches to packages for which source
 distribution is required).
 When you run +make legal-info+, Buildroot produces warnings in the +README+
 file to inform you of relevant material that could not be saved.

 Finally, keep in mind that the output of +make legal-info+ is based on
 declarative statements in each of the packages recipes. The Buildroot
 developers try to do their best to keep those declarative statements as
 accurate as possible, to the best of their knowledge. However, it is very
 well possible that those declarative statements are not all fully accurate
 nor exhaustive. You (or your legal department) _have_ to check the output
 of +make legal-info+ before using it as your own compliance delivery. See
 the _NO WARRANTY_ clauses (clauses 11 and 12) in the +COPYING+ file at the
 root of the Buildroot distribution.

 [[legal-info-buildroot]]
 === Complying with the Buildroot license

 Buildroot itself is an open source software, released under the
 http://www.gnu.org/licenses/old-licenses/gpl-2.0.html[GNU General
 Public License, version 2] or (at your option) any later version, with
 the exception of the package patches detailed below.
 However, being a build system, it is not normally part of the end product:
 if you develop the root filesystem, kernel, bootloader or toolchain for a
 device, the code of Buildroot is only present on the development machine, not
 in the device storage.

 Nevertheless, the general view of the Buildroot developers is that you should
 release the Buildroot source code along with the source code of other packages
 when releasing a product that contains GPL-licensed software.
 This is because the
 http://www.gnu.org/licenses/old-licenses/gpl-2.0.html[GNU GPL]
 defines the "'complete source code'" for an executable work as "'all the
 source code for all modules it contains, plus any associated interface
 definition files, plus the scripts used to control compilation and installation
 of the executable'".
 Buildroot is part of the 'scripts used to control compilation and
 installation of the executable', and as such it is considered part of the
 material that must be redistributed.

 Keep in mind that this is only the Buildroot developers' opinion, and you
 should consult your legal department or lawyer in case of any doubt.

 ==== Patches to packages

 Buildroot also bundles patch files, which are applied to the sources
 of the various packages. Those patches are not covered by the license
 of Buildroot. Instead, they are covered by the license of the software
 to which the patches are applied. When said software is available
 under multiple licenses, the Buildroot patches are only provided under
 the publicly accessible licenses.

 See xref:patch-policy[] for the technical details.
	// -- mode:doc; --
	// vim: set syntax=asciidoc:

	[[legal-info]]

	== Legal notice and licensing

	=== Complying with open source licenses

	All of the end products of Buildroot (toolchain, root filesystem, kernel,
	bootloaders) contain open source software, released under various licenses.

	Using open source software gives you the freedom to build rich embedded
	systems, choosing from a wide range of packages, but also imposes some
	obligations that you must know and honour.
	Some licenses require you to publish the license text in the documentation of
	your product. Others require you to redistribute the source code of the
	software to those that receive your product.

	The exact requirements of each license are documented in each package, and
	it is your responsibility (or that of your legal office) to comply with those
	requirements.
	To make this easier for you, Buildroot can collect for you some material you
	will probably need. To produce this material, after you have configured
	Buildroot with +make menuconfig+, +make xconfig+ or +make gconfig+, run:

	--------------------
	make legal-info
	--------------------

	Buildroot will collect legally-relevant material in your output directory,
	under the +legal-info/+ subdirectory.
	There you will find:

	* A +README+ file, that summarizes the produced material and contains warnings
	about material that Buildroot could not produce.
	* +buildroot.config+: this is the Buildroot configuration file that is usually
	produced with +make menuconfig+, and which is necessary to reproduce the
	build.
	* The source code for all packages; this is saved in the +sources/+ and
	+host-sources/+ subdirectories for target and host packages respectively.
	The source code for packages that set +<PKG>_REDISTRIBUTE = NO+ will not be
	saved.
	Patches that were applied are also saved, along with a file named +series+
	that lists the patches in the order they were applied. Patches are under the
	same license as the files that they modify.
	Note: Buildroot applies additional patches to Libtool scripts of
	autotools-based packages. These patches can be found under
	+support/libtool+ in the Buildroot source and, due to technical
	limitations, are not saved with the package sources. You may need to
	collect them manually.
	* A manifest file (one for host and one for target packages) listing the
	configured packages, their version, license and related information.
	Some of this information might not be defined in Buildroot; such items are
	marked as "unknown".
	* The license texts of all packages, in the +licenses/+ and +host-licenses/+
	subdirectories for target and host packages respectively.
	If the license file(s) are not defined in Buildroot, the file is not produced
	and a warning in the +README+ indicates this.

	Please note that the aim of the +legal-info+ feature of Buildroot is to
	produce all the material that is somehow relevant for legal compliance with the
	package licenses. Buildroot does not try to produce the exact material that
	you must somehow make public. Certainly, more material is produced than is
	needed for a strict legal compliance. For example, it produces the source code
	for packages released under BSD-like licenses, that you are not required to
	redistribute in source form.

	Moreover, due to technical limitations, Buildroot does not produce some
	material that you will or may need, such as the toolchain source code and the
	Buildroot source code itself (including patches to packages for which source
	distribution is required).
	When you run +make legal-info+, Buildroot produces warnings in the +README+
	file to inform you of relevant material that could not be saved.

	Finally, keep in mind that the output of +make legal-info+ is based on
	declarative statements in each of the packages recipes. The Buildroot
	developers try to do their best to keep those declarative statements as
	accurate as possible, to the best of their knowledge. However, it is very
	well possible that those declarative statements are not all fully accurate
	nor exhaustive. You (or your legal department) _have_ to check the output
	of +make legal-info+ before using it as your own compliance delivery. See
	the _NO WARRANTY_ clauses (clauses 11 and 12) in the +COPYING+ file at the
	root of the Buildroot distribution.

	[[legal-info-buildroot]]
	=== Complying with the Buildroot license

	Buildroot itself is an open source software, released under the
	http://www.gnu.org/licenses/old-licenses/gpl-2.0.html[GNU General
	Public License, version 2] or (at your option) any later version, with
	the exception of the package patches detailed below.
	However, being a build system, it is not normally part of the end product:
	if you develop the root filesystem, kernel, bootloader or toolchain for a
	device, the code of Buildroot is only present on the development machine, not
	in the device storage.

	Nevertheless, the general view of the Buildroot developers is that you should
	release the Buildroot source code along with the source code of other packages
	when releasing a product that contains GPL-licensed software.
	This is because the
	http://www.gnu.org/licenses/old-licenses/gpl-2.0.html[GNU GPL]
	defines the "'complete source code'" for an executable work as "'all the
	source code for all modules it contains, plus any associated interface
	definition files, plus the scripts used to control compilation and installation
	of the executable'".
	Buildroot is part of the 'scripts used to control compilation and
	installation of the executable', and as such it is considered part of the
	material that must be redistributed.

	Keep in mind that this is only the Buildroot developers' opinion, and you
	should consult your legal department or lawyer in case of any doubt.

	==== Patches to packages

	Buildroot also bundles patch files, which are applied to the sources
	of the various packages. Those patches are not covered by the license
	of Buildroot. Instead, they are covered by the license of the software
	to which the patches are applied. When said software is available
	under multiple licenses, the Buildroot patches are only provided under
	the publicly accessible licenses.

	See xref:patch-policy[] for the technical details.