Re: [PATCH v2] checkpatch: fix false positives in REPEATED_WORD warning

From: Joe Perches
Date: Thu Oct 22 2020 - 12:11:04 EST


On Thu, 2020-10-22 at 20:20 +0530, Aditya Srivastava wrote:
> Presence of hexadecimal address or symbol results in false warning
> message by checkpatch.pl.
[]
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -3051,7 +3051,10 @@ sub process {
> }
>
> # check for repeated words separated by a single space
> - if ($rawline =~ /^\+/ || $in_commit_log) {
> +# avoid false positive from list command eg, '-rw-r--r-- 1 root root'
> + if (($rawline =~ /^\+/ || $in_commit_log) &&
> + $rawline !~ /[bcCdDlMnpPs\?-][rwxsStT-]{9}/) {

Alignment and use \b before and after the regex please.

if (($rawline =~ /^\+/ || $in_commit_log) &&
$rawline !~ /\b[bcCdDlMnpPs\?-][rwxsStT-]{9}\b/) {
> @@ -3065,6 +3068,34 @@ sub process {
> next if ($first ne $second);
> next if ($first eq 'long');
>
> + # avoid repeating hex occurrences like 'ff ff fe 09 ...'
> + if ($first =~ /\b[0-9a-f]{2,}/) {
> + # if such sequence occurs more than 4, it is most probably part of some of code
> + next if ((scalar @hex_seq)>4);
> + # for hex occurrences which are less than 4
> + # get first hex word in the line
> + if ($rawline =~ /\b[0-9a-f]{2,} /) {
> + my $post_hex_seq = $';
> +
> + # set suffieciently high default values to avoid ignoring or counting in absence of another
> + my $non_hex_char_pos = 1000;
> + my $special_chars_pos = 500;
> +
> + if ($post_hex_seq =~ /[g-z]+/) {
> + # first non hex character in post_hex_seq
> + $non_hex_char_pos = $-[0];
> + }
> + if($post_hex_seq =~ /[^a-zA-Z0-9]{2,}/) {
> + # first occurrence of 2 or more special chars
> + $special_chars_pos = $-[0];
> + }

What does all this code actually avoid?