Re: [PATCH v4] checkpatch.pl: Add SPDX license tag check

[Joe Perches]

On Thu, 2017-12-21 at 11:04 -0600, Rob Herring wrote:
> Okay, here's what I've ended up with:
> 
> 		if ($realline == $checklicenseline) {
> 			if ($realfile =~ /\.(?:sh|pl|py)/ && $rawline =~ /\[ \+]\s*\!\#/) {
> 				$checklicenseline = 2;
> 			} elsif ($rawline =~ /^\+/) {
> 				my $comment = "";
> 				if ($realfile =~ /\.(h|s|S)$/) {
> 					$comment = '/\*';
> 				} elsif ($realfile =~ /\.(c|dts|dtsi)$/) {
> 					$comment = '//';
> 				} elsif ($realfile =~ /\.(sh|pl|py)$/) {
> 					$comment = '#';
> 				} elsif ($realfile =~ /\.rst$/) {
> 					$comment = '\.\.';
> 				}
> 
> 				if ($comment !~ /^$/ &&
> 				    $rawline !~ m@^\+$comment SPDX-License-Identifier: @) {
> 					WARN("SPDX_LICENSE_TAG",
> 					     "Missing or malformed SPDX-License-Identifier tag in 1st (or 2nd for scripts) line\n" . 
> $herecurr);
> 				}
> 			}
> 		}

Seems sensible enough.

Maybe it's better to use \Q$comment\E and a consistent
style on comment and rawline

Any checkpatch patch for license style requirements should
not be applied until after Documentation/license-rules.rst
is in -next.