Updating deprecated SPDX license headers

[badcf00d]

In the 3.0 release of the SPDX license list the use of just GPL-x.x or GPL-x.x+ was deprecated in favor of specifying GPL-x.x-only or GPL-x.x-or-later.

I wrote a script to go through and update the outdated headers:

find . -type f -print0 | xargs -0 -I % perl -pi -e \
 's/(SPDX-License-Identifier:.*GPL-\d\.\d(?!(-only|-or-later|\+)))/$1-only/g' %

find . -type f -print0 | xargs -0 -I % perl -pi -e \
 's/(SPDX-License-Identifier:.*GPL-\d\.\d)(\+)/$1-or-later/g' %

The first regex statement is to replace GPL-x.x with GPL-x.x-only. It looks for SPDX-License-Identifier: followed by 0 or more of any characters except new lines, followed by GPL-{digit}.{digit}, and then a negative lookahead to discard the match if it is followed by -only or -or-later to ignore headers that have already been updated. The matched statement is appended with -only by taking the capture group 1 followed by -only with $1-only.

The second regex statement is to replace GPL-x.x+ with GPL-x.x-or-later. It looks for SPDX-License-Identifier: followed by 0 or more of any characters except new lines, followed by GPL-{digit}.{digit}+. The statement is split into 2 capture groups so that the + character can be thrown away before appending -or-later with $1-or-later.

[KernelPRBot]

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• Working with the kernel development community - the official documentation for new kernel contributors

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[badcf00d]

Doesn't look like a practical change