[RFC v2] checkpatch: detect missing changes to trace-events

[Claudio Fontana <cfontana@suse.de>]

Signed-off-by: Claudio Fontana <cfontana@suse.de>
---
 scripts/checkpatch.pl | 37 ++++++++++++++++++++++++++++++-------
 1 file changed, 30 insertions(+), 7 deletions(-)

v1 -> v2 :

* track the "from" file in addition to the "to" file,
  and grep into both (if they exist), looking for trace.h, trace-root.h

  If files are reachable and readable, emit a warning if there is no
  update to trace-events.


diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index bd3faa154c..37db212fc6 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1300,6 +1300,7 @@ sub process {
 	my $in_header_lines = $file ? 0 : 1;
 	my $in_commit_log = 0;		#Scanning lines before patch
 	my $reported_maintainer_file = 0;
+	my $reported_trace_events_file = 0;
 	my $non_utf8_charset = 0;
 
 	our @report = ();
@@ -1309,6 +1310,7 @@ sub process {
 	our $cnt_chk = 0;
 
 	# Trace the real file/line as we go.
+	my $fromfile = '';
 	my $realfile = '';
 	my $realline = 0;
 	my $realcnt = 0;
@@ -1454,10 +1456,15 @@ sub process {
 		$here = "#$realline: " if ($file);
 
 		# extract the filename as it passes
-		if ($line =~ /^diff --git.*?(\S+)$/) {
-			$realfile = $1;
-			$realfile =~ s@^([^/]*)/@@ if (!$file);
+		if ($line =~ /^diff --git.*?(\S+).*?(\S+)$/) {
+			$fromfile = $1;
+			$realfile = $2;
+			if (!$file) {
+				$fromfile =~ s@^([^/]*)/@@ ;
+				$realfile =~ s@^([^/]*)/@@ ;
+			}
 	                checkfilename($realfile, \$acpi_testexpected, \$acpi_nontestexpected);
+
 		} elsif ($line =~ /^\+\+\+\s+(\S+)/) {
 			$realfile = $1;
 			$realfile =~ s@^([^/]*)/@@ if (!$file);
@@ -1470,6 +1477,11 @@ sub process {
 			}
 
 			next;
+
+		} elsif ($line =~ /^---\s+(\S+)/) {
+			$fromfile = $1;
+			$fromfile =~ s@^([^/]*)/@@ if (!$file);
+			next;
 		}
 
 		$here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
@@ -1524,15 +1536,26 @@ sub process {
 		if ($line =~ /^\s*MAINTAINERS\s*\|/) {
 			$reported_maintainer_file = 1;
 		}
-
+# similar check for trace-events
+		if ($line =~ /^\s*trace-events\s*\|/) {
+			$reported_trace_events_file = 1;
+		}
 # Check for added, moved or deleted files
-		if (!$reported_maintainer_file && !$in_commit_log &&
+		if (!$in_commit_log &&
 		    ($line =~ /^(?:new|deleted) file mode\s*\d+\s*$/ ||
 		     $line =~ /^rename (?:from|to) [\w\/\.\-]+\s*$/ ||
 		     ($line =~ /\{\s*([\w\/\.\-]*)\s*\=\>\s*([\w\/\.\-]*)\s*\}/ &&
 		      (defined($1) || defined($2))))) {
-			$reported_maintainer_file = 1;
-			WARN("added, moved or deleted file(s), does MAINTAINERS need updating?\n" . $herecurr);
+			if (!$reported_maintainer_file) {
+				$reported_maintainer_file = 1;
+				WARN("added, moved or deleted file(s), does MAINTAINERS need updating?\n" . $herecurr);
+			}
+			if (!$reported_trace_events_file) {
+				if (`grep -F -s -e trace.h -e trace-root.h ${fromfile} ${realfile}` ne '') {
+					$reported_trace_events_file = 1;
+					WARN("added, moved or deleted file(s), does trace-events need updating?\n" . $herecurr);
+				}
+			}
 		}
 
 # Check for wrappage within a valid hunk of the file
-- 
2.16.4