[Qemu-devel] [PATCH] checkpatch: warn about missing MAINTAINERS file changes

[Stefan Hajnoczi <stefanha@redhat.com>]

Warn if files are added/renamed/deleted without MAINTAINERS file
changes.  This has helped me in Linux and we could benefit from this
check in QEMU.

This patch is a manual cherry-pick of Linux commit
13f1937ef33950b1112049972249e6191b82e6c9 ("checkpatch: emit a warning on
file add/move/delete") by Joe Perches <joe@perches.com>.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
Note the 80-char lines are from upstream code.  Keep them as-is.

 scripts/checkpatch.pl | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index d1fe79bcc4..d0d8f63d48 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1177,6 +1177,7 @@ sub process {
 	our $clean = 1;
 	my $signoff = 0;
 	my $is_patch = 0;
+	my $reported_maintainer_file = 0;
 
 	our @report = ();
 	our $cnt_lines = 0;
@@ -1379,6 +1380,24 @@ sub process {
 			}
 		}
 
+# Check if MAINTAINERS is being updated.  If so, there's probably no need to
+# emit the "does MAINTAINERS need updating?" message on file add/move/delete
+		if ($line =~ /^\s*MAINTAINERS\s*\|/) {
+			$reported_maintainer_file = 1;
+		}
+
+# Check for added, moved or deleted files
+		if (!$reported_maintainer_file &&
+		    ($line =~ /^(?:new|deleted) file mode\s*\d+\s*$/ ||
+		     $line =~ /^rename (?:from|to) [\w\/\.\-]+\s*$/ ||
+		     ($line =~ /\{\s*([\w\/\.\-]*)\s*\=\>\s*([\w\/\.\-]*)\s*\}/ &&
+		      (defined($1) || defined($2))))) {
+			$is_patch = 1;
+			$reported_maintainer_file = 1;
+			WARN("added, moved or deleted file(s), does MAINTAINERS need updating?\n" .
+				$herecurr);
+		}
+
 # Check for wrappage within a valid hunk of the file
 		if ($realcnt != 0 && $line !~ m{^(?:\+|-| |\\ No newline|$)}) {
 			ERROR("patch seems to be corrupt (line wrapped?)\n" .
-- 
2.14.3