linux-kernel - [PATCH] checkpatch: Warn on comparisons to true and false

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1365563834.27174.12.camel@joe-AO722>
Date:	Tue, 09 Apr 2013 20:17:14 -0700
From:	Joe Perches <joe@...ches.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Andy Whitcroft <apw@...dowen.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Jacob Pan <jacob.jun.pan@...ux.intel.com>
Subject: [PATCH] checkpatch: Warn on comparisons to true and false

Comparisons of A to true and false are better written
as A and !A.

Bleat a message on use.

Signed-off-by: Joe Perches <joe@...ches.com>
---
 scripts/checkpatch.pl | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3fb6d86..080e7f6 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3538,6 +3538,23 @@ sub process {
 			     "Using yield() is generally wrong. See yield() kernel-doc (sched/core.c)\n"  . $herecurr);
 		}
 
+# check for comparisons against true and false
+		if ($line =~ /\+\s*(.*?)($Lval)\s*(==|\!=)\s*(true|false)\b(.*)$/i) {
+			my $lead = $1;
+			my $arg = $2;
+			my $test = $3;
+			my $otype = $4;
+			my $trail = $5;
+			my $type = lc($otype);
+			my $op = "!";
+			if (("$test" eq "==" && "$type" eq "true") ||
+			    ("$test" eq "!=" && "$type" eq "false")) {
+				$op = "";
+			}
+			WARN("BOOL_COMPARISON",
+			     "Using comparison to $otype is poor style. Use '${lead}${op}${arg}${trail}'\n" . $herecurr);
+		}
+
 # check for semaphores initialized locked
 		if ($line =~ /^.\s*sema_init.+,\W?0\W?\)/) {
 			WARN("CONSIDER_COMPLETION",


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/