[PATCH 1/1] scripts: check commit message length to fit 75 characters

[PATCH 1/1] scripts: check commit message length to fit 75 characters

[Denis V. Lunev]

There are a lot of commits descriptions which are rendered in the
'git log' with line wrap. Apparently, this is looking awkward. Let us
add check into checkpatch.pl for that.

I am not very good Perl developer, but there is an implementation in
Linux kernel's checkpatch.pl. Linux kernel people have faced a lot of
obstacles here thus direct port from them looks beneficial.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Alexey Kardashevskiy <aik@ozlabs.ru>
CC: "Philippe Mathieu-Daudé" <f4bug@amsat.org>
CC: "Marc-André Lureau" <marcandre.lureau@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
---
 roms/SLOF             |  2 +-
 scripts/checkpatch.pl | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/roms/SLOF b/roms/SLOF
index 6b6c16b4b4..5b4c5acdcd 160000
--- a/roms/SLOF
+++ b/roms/SLOF
@@ -1 +1 @@
-Subproject commit 6b6c16b4b40763507cf1f518096f3c3883c5cf2d
+Subproject commit 5b4c5acdcd552a4e1796aeca6bb700f6cbb0282d
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index d900d18048..dc5841a1aa 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -36,6 +36,18 @@ my $root;
 my %debug;
 my $help = 0;
 
+our $signature_tags = qr{(?xi:
+        Signed-off-by:|
+        Co-developed-by:|
+        Acked-by:|
+        Tested-by:|
+        Reviewed-by:|
+        Reported-by:|
+        Suggested-by:|
+        To:|
+        Cc:
+)};
+
 sub help {
 	my ($exitcode) = @_;
 
@@ -1303,6 +1315,7 @@ sub process {
 
 	my $in_header_lines = $file ? 0 : 1;
 	my $in_commit_log = 0;		#Scanning lines before patch
+    my $commit_log_long_line = 0;
 	my $reported_maintainer_file = 0;
 	my $non_utf8_charset = 0;
 
@@ -1585,6 +1598,19 @@ sub process {
 			WARN("8-bit UTF-8 used in possible commit log\n" . $herecurr);
 		}
 
+        if ($in_commit_log && !$commit_log_long_line && length($line) > 75 &&
+                !($line =~ /^\s*[a-zA-Z0-9_\/\.]+\s+\|\s+\d+/ ||
+                            # file delta changes
+                    $line =~ /^\s*(?:[\w\.\-\+]*\/)++[\w\.\-\+]+:/ ||
+                            # filename then :
+                    $line =~ /^\s*(?:Fixes:|Link:|$signature_tags)/i
+                            # A Fixes: or Link: line or signature tag line
+                    )) {
+            WARN("Possible unwrapped commit description (prefer a maximum " .
+                 "75 chars per line)\n" . $herecurr);
+            $commit_log_long_line = 1;
+        }
+
 # ignore non-hunk lines and lines being removed
 		next if (!$hunk_line || $line =~ /^-/);
 
-- 
2.34.1