checkpatch: always parse orig_commit in fixes tag

Do not require the presence of `$balanced_parens` to get the commit SHA;
this allows a `Fixes: deadbeef` tag to get a correct suggestion rather
than a suggestion containing a reference to HEAD.

Given this patch:

: From: Tamir Duberstein <tamird@gmail.com>
: Subject: Test patch
: Date: Fri, 25 Oct 2024 19:30:51 -0400
:
: This is a test patch.
:
: Fixes: bd17e036b495
: Signed-off-by: Tamir Duberstein <tamird@gmail.com>
: --- /dev/null
: +++ b/new-file
: @@ -0,0 +1 @@
: +Test.

Before:

WARNING: Please use correct Fixes: style 'Fixes: <12 chars of sha1> ("<title line>")' - ie: 'Fixes: c10a7d25e68f ("Test patch")'

After:

WARNING: Please use correct Fixes: style 'Fixes: <12 chars of sha1> ("<title line>")' - ie: 'Fixes: bd17e036b495 ("checkpatch: warn for non-standard fixes tag style")'

The prior behavior incorrectly suggested the patch's own SHA and title
line rather than the referenced commit's.  This fixes that.

Ironically this:

Fixes: bd17e036b495 ("checkpatch: warn for non-standard fixes tag style")
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Louis Peens <louis.peens@corigine.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Cc: Philippe Schenker <philippe.schenker@toradex.com>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 4427572..b03d526 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3209,36 +3209,31 @@ sub process {
 
 # Check Fixes: styles is correct
                if (!$in_header_lines &&
-                   $line =~ /^\s*fixes:?\s*(?:commit\s*)?[0-9a-f]{5,}\b/i) {
-                       my $orig_commit = "";
-                       my $id = "0123456789ab";
-                       my $title = "commit title";
-                       my $tag_case = 1;
-                       my $tag_space = 1;
-                       my $id_length = 1;
-                       my $id_case = 1;
+                   $line =~ /^\s*(fixes:?)\s*(?:commit\s*)?([0-9a-f]{5,40})(?:\s*($balanced_parens))?/i) {
+                       my $tag = $1;
+                       my $orig_commit = $2;
+                       my $title;
                        my $title_has_quotes = 0;
                        $fixes_tag = 1;
-
-                       if ($line =~ /(\s*fixes:?)\s+([0-9a-f]{5,})\s+($balanced_parens)/i) {
-                               my $tag = $1;
-                               $orig_commit = $2;
-                               $title = $3;
-
-                               $tag_case = 0 if $tag eq "Fixes:";
-                               $tag_space = 0 if ($line =~ /^fixes:? [0-9a-f]{5,} ($balanced_parens)/i);
-
-                               $id_length = 0 if ($orig_commit =~ /^[0-9a-f]{12}$/i);
-                               $id_case = 0 if ($orig_commit !~ /[A-F]/);
-
+                       if (defined $3) {
                                # Always strip leading/trailing parens then double quotes if existing
-                               $title = substr($title, 1, -1);
+                               $title = substr($3, 1, -1);
                                if ($title =~ /^".*"$/) {
                                        $title = substr($title, 1, -1);
                                        $title_has_quotes = 1;
                                }
+                       } else {
+                               $title = "commit title"
                        }
 
+
+                       my $tag_case = not ($tag eq "Fixes:");
+                       my $tag_space = not ($line =~ /^fixes:? [0-9a-f]{5,40} ($balanced_parens)/i);
+
+                       my $id_length = not ($orig_commit =~ /^[0-9a-f]{12}$/i);
+                       my $id_case = not ($orig_commit !~ /[A-F]/);
+
+                       my $id = "0123456789ab";
                        my ($cid, $ctitle) = git_commit_info($orig_commit, $id,
                                                             $title);