[PATCH v3] checkpatch: allow URL >80 chars

[Andreas Brauchli <a.brauchli@elementarea.net>]

Allow URL to exceed the 80 char limit for improved interaction in
adaption to ongoing but undocumented practice.

$ git grep -E '://\S{77}.*' -- '*.[ch]'

The patch checks that the URL is indeed on its own line in that
only non-word (\W) and underscore characters are allowed beside the
URL (e.g. ' /* _https://..._ */')

As per RFC3986 [1], the URL format allows for alphanum, +, - and .
characters in the scheme before the separator :// as long as it starts
with a letter (e.g. https, git, f.-+).

Recognition of URIs without more context information is prone to false
positives and thus currently left out of the heuristics.

$rawline is used in the check as comments are removed from $line.

[1] https://tools.ietf.org/html/rfc3986#section-3.1

Signed-off-by: Andreas Brauchli <andreas.brauchli@sensirion.com>
---
 scripts/checkpatch.pl | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 95cda3ecc66b..ac223921f7e0 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2906,6 +2906,10 @@ sub process {
 				 $line =~ /^\+\s*(?:\w+)?\s*DEFINE_PER_CPU/) {
 				$msg_type = "";
 
+			# URL (w/ non-word char padding e.g. " /* */")
+			} elsif ($rawline =~ /^\+[\W_]*?\b([a-z][\w\.\+\-]*:\/\/\S+[^\s\)\]\.">;,])[\W_]*$/i) {
+				$msg_type = "";
+
 			# Otherwise set the alternate message types
 
 			# a comment starts before $max_line_length
-- 
2.14.1