[PATCH v2] checkpatch: Check block comments outside of net

[Matthijs Kooijman <matthijs@stdin.nl>]

There was some code checking block comments in net/ and drivers/net/,
but nothing for regular comments.

The end of a block comment is the same as inside net, so that check can
just be generalized.

The start of block comment must not have any comment after the leading
/*, which requires a new check.

Tested with:

$ cat test.c
/* foo */

/*
 * foo
 */

/* foo
 */

/* foo
 * bar */

/**
 * foo
 * bar
 */

/****************************
 * some long block comment
 ****************************/

struct foo {
        int bar;        /* another test */
};

$ ./scripts/checkpatch.pl -f test.c
WARNING: block comments put the leading /* on a separate line
+
+/* foo

WARNING: block comments put the leading /* on a separate line
+
+/* foo

WARNING: block comments put the trailing */ on a separate line
+ * bar */

WARNING: block comments put the leading /* on a separate line
+
+/**

WARNING: block comments put the leading /* on a separate line
+
+/****************************

total: 0 errors, 5 warnings, 25 lines checked
Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
---
 scripts/checkpatch.pl | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

Note that this patch rejects /** comments, since those are not mentioned
in Codingstyle. They are used in practice though (around 1000 occurences
in kernel/ alone), so perhaps they should be allowed and documented?

Also, the new check only fires when the previous line is empty, just
like the start of block comment check for net/. However, I couldn't find
any documentation on why this restriction is needed?

v2 makes a change to the error message and adds a comment I forgot to
commit when creating this patch.

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index b28cc38..458cdbf 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1884,13 +1884,21 @@ sub process {
 			     "networking block comments don't use an empty /* line, use /* Comment...\n" . $hereprev);
 		}
 
-		if ($realfile =~ m@^(drivers/net/|net/)@ &&
-		    $rawline !~ m@^\+[ \t]*\*/[ \t]*$@ &&	#trailing */
+		if ($realfile !~ m@^(drivers/net/|net/)@ &&
+		    $rawline !~ m@^\+.*/\*.*\*/[ \t]*$@ &&	#inline /*...*/
+		    $rawline !~ /^\+[ \t]*\/\*[ \t]*$/ &&	#blank /*
+		    $rawline =~ /^\+[ \t]*\/\*.+$/ &&		#non blank /*
+		    $prevrawline =~ /^\+[ \t]*$/) {
+			WARN("BLOCK_COMMENT_STYLE",
+			     "block comments put the leading /* on a separate line\n" . $hereprev);
+		}
+
+		if ($rawline !~ m@^\+[ \t]*\*/[ \t]*$@ &&	#trailing */
 		    $rawline !~ m@^\+.*/\*.*\*/[ \t]*$@ &&	#inline /*...*/
 		    $rawline !~ m@^\+.*\*{2,}/[ \t]*$@ &&	#trailing **/
 		    $rawline =~ m@^\+[ \t]*.+\*\/[ \t]*$@) {	#non blank */
-			WARN("NETWORKING_BLOCK_COMMENT_STYLE",
-			     "networking block comments put the trailing */ on a separate line\n" . $herecurr);
+			WARN("BLOCK_COMMENT_STYLE",
+			     "block comments put the trailing */ on a separate line\n" . $herecurr);
 		}
 
 # check for spaces at the beginning of a line.
-- 
1.8.0