cstyle: allow right paren on its own line

Make the style checker script accept right parentheses on their own
lines. This is motivated by the Linux tracepoints macro
DECLARE_EVENT_CLASS.

The code within TP_fast_assign() (a parameter of DECLARE_EVENT_CLASS)
is normal C assignments terminated by semicolons.  But the style
checker forbids us from following a semicolon with a non-blank and
from preceding a right parenthesis with white space.  Therefore the
closing parenthesis must go on the next line, yet the style checker
foribs us from indenting it for readability.  Relaxing the
no-non-blank-after-semicolon rule would open the door to too many bad
style practices. So instead we relax the
no-white-space-before-right-paren rule if the parenthesis is on its
own line.  The relaxation is overriden with the -p option so we still
have a way to catch misuse of this style.

Signed-off-by: Ned Bass <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>

scripts/cstyle.pl

@@ -597,8 +597,9 @@ ($$)
 	if (/\(\s/) {
 		err("whitespace after left paren");
 	}
-	# allow "for" statements to have empty "continue" clauses
-	if (/\s\)/ && !/^\s*for \([^;]*;[^;]*; \)/) {
+	# Allow "for" statements to have empty "continue" clauses.
+	# Allow right paren on its own line unless we're being picky (-p).
+	if (/\s\)/ && !/^\s*for \([^;]*;[^;]*; \)/ && ($picky || !/^\s*\)/)) {
 		err("whitespace before right paren");
 	}
 	if (/^\s*\(void\)[^ ]/) {