From: Joe Perches <joe@perches.com>
Date: Thu, 16 Apr 2015 19:44:36 +0000 (-0700)
Subject: checkpatch: add 'Prefer ARRAY_SIZE" test
X-Git-Tag: v4.1-rc1~102^2~107
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=b598b67060f14eb8c34d0cef1db4727dab56ef91;p=linux.git

checkpatch: add 'Prefer ARRAY_SIZE" test

Add a test for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo).

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index ea628ebfa20e..6c11cb61e9f4 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3227,6 +3227,19 @@ sub process {
 				$herecurr);
                }
 
+# check for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo)
+		if ($line =~ m@\bsizeof\s*\(\s*($Lval)\s*\)@) {
+			my $array = $1;
+			if ($line =~ m@\b(sizeof\s*\(\s*\Q$array\E\s*\)\s*/\s*sizeof\s*\(\s*\Q$array\E\s*\[\s*0\s*\]\s*\))@) {
+				my $array_div = $1;
+				if (WARN("ARRAY_SIZE",
+					 "Prefer ARRAY_SIZE($array)\n" . $herecurr) &&
+				    $fix) {
+					$fixed[$fixlinenr] =~ s/\Q$array_div\E/ARRAY_SIZE($array)/;
+				}
+			}
+		}
+
 # check for function declarations without arguments like "int foo()"
 		if ($line =~ /(\b$Type\s+$Ident)\s*\(\s*\)/) {
 			if (ERROR("FUNCTION_WITHOUT_ARGS",