From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753391Ab3LMTG2 (ORCPT ); Fri, 13 Dec 2013 14:06:28 -0500 Received: from smtprelay0052.hostedemail.com ([216.40.44.52]:46288 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752606Ab3LMTG0 (ORCPT ); Fri, 13 Dec 2013 14:06:26 -0500 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::::::::,RULES_HIT:41:355:379:541:800:960:973:982:988:989:1260:1261:1277:1311:1313:1314:1345:1373:1437:1515:1516:1518:1534:1543:1593:1594:1711:1730:1747:1777:1792:2198:2199:2393:2559:2562:2828:2898:3138:3139:3140:3141:3142:3354:3653:3865:3866:3867:3868:3870:3871:3872:3874:4321:5007:7652:7688:7903:10004:10400:10848:11026:11232:11658:11914:12043:12291:12296:12438:12517:12519:12555:13161:13229:21060,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0 X-HE-Tag: fan50_54a0a512a7a2a X-Filterd-Recvd-Size: 3903 Message-ID: <1386961580.2479.42.camel@joe-AO722> Subject: [PATCH] checkpatch: Attempt to find missing switch/case break; From: Joe Perches To: Andrew Morton Cc: Andy Whitcroft , Jiri Kosina , LKML , Benjamin Tissoires , Dave Jones Date: Fri, 13 Dec 2013 11:06:20 -0800 Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.8.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org switch case statements missing a break statement are an unfortunately common error. e.g.: commit 4a2c94c9b6c0 ("HID: kye: Add report fixup for Genius Manticore Keyboard") case blocks should end in a break/return/goto/continue. If a fall-through is used, it should have a comment showing that it is intentional. Ideally that comment should be something like: "/* fall-through */" Add a test to look for missing break statements. This looks only at the context lines before an inserted case so it's possible to have false positives when the context contains a close brace and the break is before the brace and not part of the patch context. Looking at recent patches, this is a pretty rare occurrence. The normal kernel style uses a break as the last line of the previous block. Signed-off-by: Joe Perches --- Also tested on all files in drivers/hid/ There is a hit for drivers/hid/hid-microsoft.c I've no idea what's right here but adding a break or return or a "fall-through" comment would be nicer. static int ms_ergonomy_kb_quirk(struct hid_input *hi, struct hid_usage *usage, unsigned long **bit, int *max) { struct input_dev *input = hi->input; switch (usage->hid & HID_USAGE) { case 0xfd06: ms_map_key_clear(KEY_CHAT); break; case 0xfd07: ms_map_key_clear(KEY_PHONE); break; case 0xff05: set_bit(EV_REP, input->evbit); ms_map_key_clear(KEY_F13); set_bit(KEY_F14, input->keybit); set_bit(KEY_F15, input->keybit); set_bit(KEY_F16, input->keybit); set_bit(KEY_F17, input->keybit); set_bit(KEY_F18, input->keybit); default: return 0; } return 1; } scripts/checkpatch.pl | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 38be5d5..94225d2 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -4132,6 +4132,31 @@ sub process { } } +# check for case / default statements not preceeded by break/fallthrough/switch + if ($line =~ /^.\s*(?:case\s+(?:$Ident|$Constant)\s*|default):/) { + my $has_break = 0; + my $has_statement = 0; + my $count = 0; + my $prevline = $linenr; + while ($prevline > 1 && $count < 3 && !$has_break) { + $prevline--; + my $rline = $rawlines[$prevline - 1]; + my $fline = $lines[$prevline - 1]; + last if ($fline =~ /^\@\@/); + next if ($fline =~ /^\-/); + next if ($fline =~ /^.(?:\s*(?:case\s+(?:$Ident|$Constant)[\s$;]*|default):[\s$;]*)*$/); + $has_break = 1 if ($rline =~ /fall[\s_-]*(through|thru)/i); + next if ($fline =~ /^.[\s$;]*$/); + $has_statement = 1; + $count++; + $has_break = 1 if ($fline =~ /\bswitch\b|\b(?:break\s*;[\s$;]*$|return\b|goto\b|continue\b)/); + } + if (!$has_break && $has_statement) { + WARN("MISSING_BREAK", + "Possible switch case/default not preceeded by break or fallthrough comment\n" . $herecurr); + } + } + # check for switch/default statements without a break; if ($^V && $^V ge 5.10.0 && defined $stat &&