checkpatch: add fix and improve warning msg for non-standard signature
Currently checkpatch warns for BAD_SIGN_OFF on non-standard signature
styles.
A large number of these warnings occur because of typo mistakes in
signature tags. An evaluation over v4.13..v5.8 showed that out of 539
warnings due to non-standard signatures, 87 are due to typo mistakes.
Following are the standard signature tags which are often incorrectly
used, along with their individual counts of incorrect use (over
v4.13..v5.8):
Reviewed-by: 42
Signed-off-by: 25
Reported-by: 6
Acked-by: 4
Tested-by: 4
Suggested-by: 4
Provide a fix by calculating levenshtein distance for the signature tag
with all the standard signatures and suggest a fix with a signature, whose
edit distance is less than or equal to 2 with the misspelled signature.
Out of the 86 mispelled signatures fixed with this approach, 85 were found
to be good corrections and 1 was bad correction.
Following was found to be a bad correction:
Tweeted-by (count: 1) => Tested-by
Link: https://lkml.kernel.org/r/20201128204333.7054-1-yashsri421@gmail.com
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 241c064..d7616a6 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -506,6 +506,64 @@
Cc:
)};
+sub edit_distance_min {
+ my (@arr) = @_;
+ my $len = scalar @arr;
+ if ((scalar @arr) < 1) {
+ # if underflow, return
+ return;
+ }
+ my $min = $arr[0];
+ for my $i (0 .. ($len-1)) {
+ if ($arr[$i] < $min) {
+ $min = $arr[$i];
+ }
+ }
+ return $min;
+}
+
+sub get_edit_distance {
+ my ($str1, $str2) = @_;
+ $str1 = lc($str1);
+ $str2 = lc($str2);
+ $str1 =~ s/-//g;
+ $str2 =~ s/-//g;
+ my $len1 = length($str1);
+ my $len2 = length($str2);
+ # two dimensional array storing minimum edit distance
+ my @distance;
+ for my $i (0 .. $len1) {
+ for my $j (0 .. $len2) {
+ if ($i == 0) {
+ $distance[$i][$j] = $j;
+ } elsif ($j == 0) {
+ $distance[$i][$j] = $i;
+ } elsif (substr($str1, $i-1, 1) eq substr($str2, $j-1, 1)) {
+ $distance[$i][$j] = $distance[$i - 1][$j - 1];
+ } else {
+ my $dist1 = $distance[$i][$j - 1]; #insert distance
+ my $dist2 = $distance[$i - 1][$j]; # remove
+ my $dist3 = $distance[$i - 1][$j - 1]; #replace
+ $distance[$i][$j] = 1 + edit_distance_min($dist1, $dist2, $dist3);
+ }
+ }
+ }
+ return $distance[$len1][$len2];
+}
+
+sub find_standard_signature {
+ my ($sign_off) = @_;
+ my @standard_signature_tags = (
+ 'Signed-off-by:', 'Co-developed-by:', 'Acked-by:', 'Tested-by:',
+ 'Reviewed-by:', 'Reported-by:', 'Suggested-by:'
+ );
+ foreach my $signature (@standard_signature_tags) {
+ return $signature if (get_edit_distance($sign_off, $signature) <= 2);
+ }
+
+ return "";
+}
+
our @typeListMisordered = (
qr{char\s+(?:un)?signed},
qr{int\s+(?:(?:un)?signed\s+)?short\s},
@@ -2773,8 +2831,17 @@
my $ucfirst_sign_off = ucfirst(lc($sign_off));
if ($sign_off !~ /$signature_tags/) {
- WARN("BAD_SIGN_OFF",
- "Non-standard signature: $sign_off\n" . $herecurr);
+ my $suggested_signature = find_standard_signature($sign_off);
+ if ($suggested_signature eq "") {
+ WARN("BAD_SIGN_OFF",
+ "Non-standard signature: $sign_off\n" . $herecurr);
+ } else {
+ if (WARN("BAD_SIGN_OFF",
+ "Non-standard signature: '$sign_off' - perhaps '$suggested_signature'?\n" . $herecurr) &&
+ $fix) {
+ $fixed[$fixlinenr] =~ s/$sign_off/$suggested_signature/;
+ }
+ }
}
if (defined $space_before && $space_before ne "") {
if (WARN("BAD_SIGN_OFF",
