Fix problematic Unicode license check
There is an existing check named license-problem-convert-utf-code
. It looked for copies of Convert-UTF
, which was a file originally released by Unicode under a DFSG-non-free license. The license in question contained the following statement:
"Unicode, Inc. hereby grants the right to freely use the information supplied in this file in the creation of products supporting the Unicode Standard"
This is non-free because it did not allow the use of the file in ways that did not support the Unicode standard.
In 2004 Unicode relicensed their files under a new license, which is DFSG-free.
This link explains their copyright and terms of use:
http://www.unicode.org/copyright.html
It includes this link to the actual license:
https://www.unicode.org/license.txt
Convert-UTF
was extensively copied into other projects. Many of those copies were made before the license change, and the new license often has not been propagated into downstream copies. However, even when the new license was propagated, this Lintian check was still flagging the files as a false positive.
In investigating the reason why, I discovered that the Lintian check did not look for a copy of the problematic license itself. Rather, it looked for other text that occurred at the end of Convert-UTF
. This patch fixes that problem and uses logic that detects the presence of the actual problematic.
As part of testing the change, I discovered that there are other files in Debian packages that also include the problematic license. These were not flagged by previous versions of this tag. With the discovery that this problem no longer just affects Convert-UTF
, I have renamed the tag to be license-problem-old-unicode
.
Merging this patch fixes https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=854209.