From: Aditya Srivastava <yashsri421@xxxxxxxxx> Subject: 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@xxxxxxxxx Signed-off-by: Aditya Srivastava <yashsri421@xxxxxxxxx> Acked-by: Joe Perches <joe@xxxxxxxxxxx> Cc: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- scripts/checkpatch.pl | 71 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 69 insertions(+), 2 deletions(-) --- a/scripts/checkpatch.pl~checkpatch-add-fix-and-improve-warning-msg-for-non-standard-signature +++ a/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", _
