GLEP 23: Handling of ACCEPT_LICENSE

Ebuild LICENSE Variable

Most ebuilds are for software which is released under a single license. In these cases, the current LICENSE variable can remain as is. For example:

LICENSE="single-license"

However, there are several ebuilds for software which is released under several licenses, of which the user must accept one, some or all [2]. To complicate this, some ebuilds include optional components which fall under a different license.

To accommodate these cases, LICENSE syntax should accommodate all functionality offered by a DEPEND string. To keep things simple, this GLEP proposes that the syntax be identical. For example:

LICENSE="mandatory-license
    || ( choosable-licence1 chooseable-license-2 )
    useflag? ( optional-component-license )"

License names may contain [a-zA-Z0-9] (english alphanumeric characters), _ (underscore), - (hyphen), . (dot) and + (plus sign). They must not begin with a hyphen, a dot or a plus sign.

License Groups

Almost all users are willing to install any software that is FSF-approved. Other users are willing to install any software and implicitly accept its license. To this end, implementations will also need to handle grouping of licenses.

At a minimum, there needs to be the groups GPL-COMPATIBLE, FSF-APPROVED, OSI-APPROVED and NON-MUST-HAVE-READ. NON-MUST-HAVE-READ licenses are those that don't require manual acceptance for to be considered legally binding. This is the current behaviour of portage.

These groups are defined in a new file license_groups in the profiles subdirectory of the tree (or overlays). Details of handling groups defined in overlays is implementation dependent.

The format of this file is

<groupname> <license1> <license2> ... <licenseN>

Also any line starting with # is ignored and may be used for comments. Group names use the same syntax as normal license names. Also license groups may contain other groups. License groups may not contain negated elements, so a group

mygroup foo -bar -bla

is illegal.

ACCEPT_LICENSE

This GLEP proposes that a user be able to explicitly accept or decline licenses by editing a new variable ACCEPT_LICENSE in /etc/make.conf. Again, to keep things simple, the syntax should be similar to that of other incrementals. For example:

ACCEPT_LICENSE="-* accepted-license -declined-license"

As an extension, ACCEPT_LICENSE must also support license groups. This GLEP proposes that the license group be prepended by the special character "@". For example:

ACCEPT_LICENSE="-* @FSF-APPROVED"

License groups may be negated with the result that all elements of that group are also negated.

Portage will also offer a package.license facility to offer this functionality on a per-package base (analog to package.keywords), other implementations may implement such a facility differently or not at all.

Behaviour

Unaccepted licenses will be treated like any other masked package, that is the user interface of an implementation will display a message listing any license that has to be accepted before the package can be merged with a pointer to the exact license text.

Past versions of this document proposed to handle license-masked packages like blockers, but this would be inconsistent with other visibility filters as well as the current blocker system (as a blocker affects two packages) and be more complicated to implement.