On Sun, 2020-11-29 at 02:13 +0530, Aditya Srivastava wrote:
> Currently checkpatch warns for BAD_SIGN_OFF on non-standard signature
> styles.
Thanks.
Acked-by: Joe Perches <j...@perches.com>
> 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
>
> Signed-off-by: Aditya Srivastava <yashsri...@gmail.com>
> ---
> applies on next-20201120
>
> changes in v2: modify commit message: replace specific example with overall
> evaluation, minor changes
>
> changes in v3: summarize commit message
>
> changes in v4: improve commit message; remove signature suggestions of small
> length (ie 'cc' and 'to')
>
> changes in v5: modify coding styles: improve function names, whitespaces
>
> changes in v6: Simplify foreach loop; change standard signature tag values to
> normal ucfirst; modify warning message
>
> scripts/checkpatch.pl | 71 +++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 69 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index fdfd5ec09be6..4a026926139f 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -506,6 +506,64 @@ our $signature_tags = qr{(?xi:
> 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 @@ sub process {
> 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",
