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
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
scripts/checkpatch.pl | 79 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 77 insertions(+), 2 deletions(-)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index fdfd5ec09be6..e372d26d03dc 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -506,6 +506,72 @@ 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);
+ $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:'
+ );
+ my $standard_signature;
+ my $min_edit_distance = 20; # setting default value
+ my $edit_distance;
+ foreach (@standard_signature_tags) {
+ $edit_distance = get_edit_distance($sign_off, $_);
+ if ($edit_distance < $min_edit_distance) {
+ $min_edit_distance = $edit_distance;
+ $standard_signature = $_;
+ }
+ }
+ if ($min_edit_distance <= 2) {
+ return ucfirst($standard_signature);
+ }
+ return "";
+}
+
our @typeListMisordered = (
qr{char\s+(?:un)?signed},
qr{int\s+(?:(?:un)?signed\s+)?short\s},
@@ -2773,8 +2839,17 @@ 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",
--
2.17.1
