add a trivial patch style checker

We are seeing increasing levels of minor patch style violations in submissions to the mailing lists as well as making it into the tree. These detract from the quality of the submission and cause unnessary work for reviewers. As a first step package up the current state of the patch style checker and include it in the kernel tree. Add instructions suggesting running it on submissions. This adds version v0.01 of the checkpatch.pl script. Signed-off-by: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Joel Schopp <jschopp@austin.ibm.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

add a trivial patch style checker
We are seeing increasing levels of minor patch style violations in submissions to the mailing lists as well as making it into the tree. These detract from the quality of the submission and cause unnessary work for reviewers. As a first step package up the current state of the patch style checker and include it in the kernel tree. Add instructions suggesting running it on submissions. This adds version v0.01 of the checkpatch.pl script. Signed-off-by: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Joel Schopp <jschopp@austin.ibm.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy Whitcroft · Linus Torvalds
1 parent bc913b1899
Showing 5 changed files with 644 additions and 13 deletions Side-by-side Diff
Documentation/SubmitChecklist
Documentation/SubmittingPatches
Documentation/feature-removal-schedule.txt
MAINTAINERS
scripts/checkpatch.pl
@@ -84,4 +84,10 @@
 24: Avoid whitespace damage such as indenting with spaces or whitespace
     at the end of lines.  You can test this by feeding the patch to
     "git apply --check --whitespace=error-all"
+
+25: Check your patch for general style as detailed in
+    Documentation/CodingStyle.  Check for trivial violations with the
+    patch style checker prior to submission (scripts/checkpatch.pl).
+    You should be able to justify all violations that remain in
+    your patch.
@@ -118,8 +118,21 @@
  
  
  
-4) Select e-mail destination.
+4) Style check your changes.
  
+Check your patch for basic style violations, details of which can be
+found in Documentation/CodingStyle.  Failure to do so simply wastes
+the reviewers time and will get your patch rejected, probabally
+without even being read.
+
+At a minimum you should check your patches with the patch style
+checker prior to submission (scripts/patchcheck.pl).  You should
+be able to justify all violations that remain in your patch.
+
+
+
+5) Select e-mail destination.
+
 Look through the MAINTAINERS file and the source code, and determine
 if your change applies to a specific subsystem of the kernel, with
 an assigned maintainer.  If so, e-mail that person.
@@ -146,7 +159,7 @@
  
  
  
-5) Select your CC (e-mail carbon copy) list.
+6) Select your CC (e-mail carbon copy) list.
  
 Unless you have a reason NOT to do so, CC linux-kernel@vger.kernel.org.
  
  
@@ -187,9 +200,8 @@
  
  
  
+7) No MIME, no links, no compression, no attachments.  Just plain text.
  
-6) No MIME, no links, no compression, no attachments.  Just plain text.
-
 Linus and other kernel developers need to be able to read and comment
 on the changes you are submitting.  It is important for a kernel
 developer to be able to "quote" your changes, using standard e-mail
  
@@ -223,9 +235,9 @@
  
  
  
-7) E-mail size.
+8) E-mail size.
  
-When sending patches to Linus, always follow step #6.
+When sending patches to Linus, always follow step #7.
  
 Large changes are not appropriate for mailing lists, and some
 maintainers.  If your patch, uncompressed, exceeds 40 kB in size,
@@ -234,7 +246,7 @@
  
  
  
-8) Name your kernel version.
+9) Name your kernel version.
  
 It is important to note, either in the subject line or in the patch
 description, the kernel version to which this patch applies.
@@ -244,7 +256,7 @@
  
  
  
-9) Don't get discouraged.  Re-submit.
+10) Don't get discouraged.  Re-submit.
  
 After you have submitted your change, be patient and wait.  If Linus
 likes your change and applies it, it will appear in the next version
@@ -270,7 +282,7 @@
  
  
  
-10) Include PATCH in the subject
+11) Include PATCH in the subject
  
 Due to high e-mail traffic to Linus, and to linux-kernel, it is common
 convention to prefix your subject line with [PATCH].  This lets Linus
@@ -279,7 +291,7 @@
  
  
  
-11) Sign your work
+12) Sign your work
  
 To improve tracking of who did what, especially with patches that can
 percolate to their final resting place in the kernel through several
  
@@ -328,8 +340,9 @@
 point out some special detail about the sign-off. 
  
  
-12) The canonical patch format
  
+13) The canonical patch format
+
 The canonical patch subject line is:
  
     Subject: [PATCH 001/123] subsystem: summary phrase
@@ -426,6 +439,10 @@
  
 Nuff said.  If your code deviates too much from this, it is likely
 to be rejected without further review, and without comment.
+
+Check your patches with the patch style checker prior to submission
+(scripts/checkpatch.pl).  You should be able to justify all
+violations that remain in your patch.
  
  
  
@@ -70,6 +70,7 @@
  
 What:	Video4Linux API 1 ioctls and video_decoder.h from Video devices.
 When:	December 2006
+Files:	include/linux/video_decoder.h
 Why:	V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6
 	series. The old API have lots of drawbacks and don't provide enough
 	means to work with all video and audio standards. The newer API is
@@ -30,9 +30,12 @@
 	job the maintainers (and especially Linus) do is to keep things
 	looking the same. Sometimes this means that the clever hack in
 	your driver to get around a problem actually needs to become a
-	generalized kernel feature ready for next time. See
-	Documentation/CodingStyle for guidance here.
+	generalized kernel feature ready for next time.
  
+	PLEASE check your patch with the automated style checker
+	(scripts/checkpatch.pl) to catch trival style violations.
+	See Documentation/CodingStyle for guidance here.
+
 	PLEASE try to include any credit lines you want added with the
 	patch. It avoids people being missed off by mistake and makes
 	it easier to know who wants adding and who doesn't.
@@ -971,6 +974,15 @@
 M:	johannes@sipsolutions.net
 L:	linux-wireless@vger.kernel.org
 S:	Maintained
+
+CHECKPATCH
+P:	Andy Whitcroft
+M:	apw@shadowen.org
+P:	Randy Dunlap
+M:	rdunlap@xenotime.net
+P:	Joel Schopp
+M:	jschopp@austin.ibm.com
+S:	Supported
  
 COMMON INTERNET FILE SYSTEM (CIFS)
 P:	Steve French
+#!/usr/bin/perl -w
+# (c) 2001, Dave Jones. <davej@codemonkey.org.uk> (the file handling bit)
+# (c) 2005, Joel Scohpp <jschopp@austin.ibm.com> (the ugly bit)
+# (c) 2007, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite, etc)
+# Licensed under the terms of the GNU GPL License version 2
+
+use strict;
+
+my $P = $0;
+
+my $V = '0.01';
+
+use Getopt::Long qw(:config no_auto_abbrev);
+
+my $quiet = 0;
+my $tree = 1;
+my $chk_signoff = 1;
+my $chk_patch = 1;
+GetOptions(
+	'q|quiet'	=> \$quiet,
+	'tree!'		=> \$tree,
+	'signoff!'	=> \$chk_signoff,
+	'patch!'	=> \$chk_patch,
+) or exit;
+
+my $exit = 0;
+
+if ($#ARGV < 0) {
+	print "usage: patchstylecheckemail.pl [options] patchfile\n";
+	print "version: $V\n";
+	print "options: -q           => quiet\n";
+	print "         --no-tree    => run without a kernel tree\n";
+	exit(1);
+}
+
+if ($tree && !top_of_kernel_tree()) {
+	print "Must be run from the top-level dir. of a kernel tree\n";
+	exit(2);
+}
+
+my @deprecated = ();
+my $removal = 'Documentation/feature-removal-schedule.txt';
+if ($tree && -f $removal) {
+	open(REMOVE, "<$removal") || die "$P: $removal: open failed - $!\n";
+	while (<REMOVE>) {
+		if (/^Files:\s+(.*\S)/) {
+			for my $file (split(/[, ]+/, $1)) {
+				if ($file =~ m@include/(.*)@) {
+					push(@deprecated, $1);
+				}
+			}
+		}
+	}
+}
+
+my @lines = ();
+while (<>) {
+	chomp;
+	push(@lines, $_);
+	if (eof(ARGV)) {
+		if (!process($ARGV, @lines)) {
+			$exit = 1;
+		}
+		@lines = ();
+	}
+}
+
+exit($exit);
+
+sub top_of_kernel_tree {
+	if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
+	    (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
+	    (-d "Documentation") && (-d "arch") && (-d "include") &&
+	    (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
+	    (-d "kernel") && (-d "lib") && (-d "scripts")) {
+		return 1;
+	}
+	return 0;
+}
+
+sub expand_tabs {
+	my ($str) = @_;
+
+	my $res = '';
+	my $n = 0;
+	for my $c (split(//, $str)) {
+		if ($c eq "\t") {
+			$res .= ' ';
+			$n++;
+			for (; ($n % 8) != 0; $n++) {
+				$res .= ' ';
+			}
+			next;
+		}
+		$res .= $c;
+		$n++;
+	}
+
+	return $res;
+}
+
+sub cat_vet {
+	my ($vet) = @_;
+
+	$vet =~ s/\t/^I/;
+	$vet =~ s/$/\$/;
+
+	return $vet;
+}
+
+sub process {
+	my $filename = shift;
+	my @lines = @_;
+
+	my $linenr=0;
+	my $prevline="";
+	my $stashline="";
+
+	my $lineforcounting='';
+	my $indent;
+	my $previndent=0;
+	my $stashindent=0;
+
+	my $clean = 1;
+	my $signoff = 0;
+	my $is_patch = 0;
+
+	# Trace the real file/line as we go.
+	my $realfile = '';
+	my $realline = 0;
+	my $realcnt = 0;
+	my $here = '';
+	my $in_comment = 0;
+	my $first_line = 0;
+
+	foreach my $line (@lines) {
+		$linenr++;
+
+#extract the filename as it passes
+		if ($line=~/^\+\+\+\s+(\S+)/) {
+			$realfile=$1;
+			$in_comment = 0;
+			next;
+		}
+#extract the line range in the file after the patch is applied
+		if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
+			$is_patch = 1;
+			$first_line = 1;
+			$in_comment = 0;
+			$realline=$1-1;
+			if (defined $2) {
+				$realcnt=$3+1;
+			} else {
+				$realcnt=1+1;
+			}
+			next;
+		}
+
+#track the line number as we move through the hunk
+		if ($line=~/^[ \+]/) {
+			$realline++;
+			$realcnt-- if ($realcnt != 0);
+
+			# track any sort of multi-line comment.  Obviously if
+			# the added text or context do not include the whole
+			# comment we will not see it. Such is life.
+			#
+			# Guestimate if this is a continuing comment.  If this
+			# is the start of a diff block and this line starts
+			# ' *' then it is very likely a comment.
+			if ($first_line and $line =~ m@^.\s*\*@) {
+				$in_comment = 1;
+			}
+			if ($line =~ m@/\*@) {
+				$in_comment = 1;
+			}
+			if ($line =~ m@\*/@) {
+				$in_comment = 0;
+			}
+
+			$lineforcounting = $line;
+			$lineforcounting =~ s/^\+//;
+			$lineforcounting = expand_tabs($lineforcounting);
+
+			my ($white) = ($lineforcounting =~ /^(\s*)/);
+			$indent = length($white);
+
+			# Track the previous line.
+			($prevline, $stashline) = ($stashline, $line);
+			($previndent, $stashindent) = ($stashindent, $indent);
+			$first_line = 0;
+		}
+
+#make up the handle for any error we report on this line
+		$here = "PATCH: $ARGV:$linenr:";
+		$here .= "\nFILE: $realfile:$realline:" if ($realcnt != 0);
+
+		my $herecurr = "$here\n$line\n\n";
+		my $hereprev = "$here\n$prevline\n$line\n\n";
+
+#check the patch for a signoff:
+		if ($line =~ /^\s*Signed-off-by:\s/) {
+			$signoff++;
+
+		} elsif ($line =~ /^\s*signed-off-by:/i) {
+			if (!($line =~ /^\s*Signed-off-by:/)) {
+				print "use Signed-off-by:\n";
+				print "$herecurr";
+				$clean = 0;
+			}
+			if ($line =~ /^\s*signed-off-by:\S/i) {
+				print "need space after Signed-off-by:\n";
+				print "$herecurr";
+				$clean = 0;
+			}
+		}
+
+#ignore lines not being added
+		if ($line=~/^[^\+]/) {next;}
+
+# check we are in a valid source file *.[hcsS] if not then ignore this hunk
+		next if ($realfile !~ /\.[hcsS]$/);
+
+#trailing whitespace
+		if ($line=~/\S\s+$/) {
+			my $herevet = "$here\n" . cat_vet($line) . "\n\n";
+			print "trailing whitespace\n";
+			print "$herevet";
+			$clean = 0;
+		}
+#80 column limit
+		if (!($prevline=~/\/\*\*/) && length($lineforcounting) > 80) {
+			print "line over 80 characters\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+# check we are in a valid source file *.[hc] if not then ignore this hunk
+		next if ($realfile !~ /\.[hc]$/);
+
+# at the beginning of a line any tabs must come first and anything
+# more than 8 must use tabs.
+		if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
+			my $herevet = "$here\n" . cat_vet($line) . "\n\n";
+			print "use tabs not spaces\n";
+			print "$herevet";
+			$clean = 0;
+		}
+
+		#
+		# The rest of our checks refer specifically to C style
+		# only apply those _outside_ comments.
+		#
+		next if ($in_comment);
+
+# no C99 // comments
+		if ($line =~ m@//@ and !($line =~ m@\".*//.*\"@)) {
+			print "do not use C99 // comments\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+		# Remove comments from the line before processing.
+		$line =~ s@/\*.*\*/@@g;
+		$line =~ s@/\*.*@@;
+		$line =~ s@.*\*/@@;
+		$line =~ s@//.*@@;
+
+#EXPORT_SYMBOL should immediately follow its function closing }.
+		if (($line =~ /EXPORT_SYMBOL.*\(.*\)/) ||
+		    ($line =~ /EXPORT_UNUSED_SYMBOL.*\(.*\)/)) {
+			if (($prevline !~ /^}/) &&
+			   ($prevline !~ /^\+}/) &&
+			   ($prevline !~ /^ }/)) {
+				print "EXPORT_SYMBOL(func); should immediately follow its function\n";
+				print "$herecurr";
+				$clean = 0;
+			}
+		}
+
+		# check for static initialisers.
+		if ($line=~/\s*static\s.*=\s+(0|NULL);/) {
+			print "do not initialise statics to 0 or NULL\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+		# check for new typedefs.
+		if ($line=~/\s*typedef\s/) {
+			print "do not add new typedefs\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+# * goes on variable not on type
+		if ($line=~/[A-Za-z\d_]+\* [A-Za-z\d_]+/) {
+			print "\"foo* bar\" should be \"foo *bar\"\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+# # no BUG() or BUG_ON()
+# 		if ($line =~ /\b(BUG|BUG_ON)\b/) {
+# 			print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
+# 			print "$herecurr";
+# 			$clean = 0;
+# 		}
+
+# printk should use KERN_* levels
+		if ($line =~ /\bprintk\((?!KERN_)/) {
+			print "printk() should include KERN_ facility level\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+#function brace can't be on same line, except for #defines of do while, or if closed on same line
+		if (($line=~/[A-Za-z\d_]+\**\s+\**[A-Za-z\d_]+\(.*\).* {/) and
+		    !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
+			print "braces following function declarations go on the next line\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+		my $opline = $line;
+		$opline =~ s/^.//;
+		if (!($line=~/\#\s*include/)) {
+			# Check operator spacing.
+			my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
+			for (my $n = 0; $n < $#elements; $n += 2) {
+				# $wN says we have white-space before or after
+				# $sN says we have a separator before or after
+				# $oN says we have another operator before or after
+				my $w1 = $elements[$n] =~ /\s$/;
+				my $s1 = $elements[$n] =~ /(\[|\(|\s)$/;
+				my $o1 = $elements[$n] eq '';
+				my $op = $elements[$n + 1];
+				my $w2 = 1;
+				my $s2 = 1;
+				my $o2 = 0;
+				# If we have something after the operator handle it.
+				if (defined $elements[$n + 2]) {
+					$w2 = $elements[$n + 2] =~ /^\s/;
+					$s2 = $elements[$n + 2] =~ /^(\s|\)|\]|;)/;
+					$o2 = $elements[$n + 2] eq '';
+				}
+
+				# Generate the context.
+				my $at = "here: ";
+				for (my $m = $n; $m >= 0; $m--) {
+					if ($elements[$m] ne '') {
+						$at .= $elements[$m];
+						last;
+					}
+				}
+				$at .= $op;
+				for (my $m = $n + 2; defined $elements[$m]; $m++) {
+					if ($elements[$m] ne '') {
+						$at .= $elements[$m];
+						last;
+					}
+				}
+
+				##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
+				# Skip things apparently in quotes.
+				next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
+
+				# We need ; as an operator.  // is a comment.
+				if ($op eq ';' or $op eq '//') {
+
+				# -> should have no spaces
+				} elsif ($op eq '->') {
+					if ($s1 or $s2) {
+						print "no spaces around that '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+
+				# , must have a space on the right.
+				} elsif ($op eq ',') {
+					if (!$s2) {
+						print "need space after that '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+
+				# unary ! and unary ~ are allowed no space on the right
+				} elsif ($op eq '!' or $op eq '~') {
+					if (!$s1 && !$o1) {
+						print "need space before that '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+					if ($s2) {
+						print "no space after that '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+
+				# unary ++ and unary -- are allowed no space on one side.
+				} elsif ($op eq '++' or $op eq '--') {
+					if (($s1 && $s2) || ((!$s1 && !$o1) && (!$s2 && !$o2))) {
+						print "need space one side of that '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+
+				# & is both unary and binary
+				# unary:
+				# 	a &b
+				# binary (consistent spacing):
+				#	a&b		OK
+				#	a & b		OK
+				#
+				# boiling down to: if there is a space on the right then there
+				# should be one on the left.
+				#
+				# - is the same
+				#
+				# * is the same only adding:
+				# type:
+				# 	(foo *)
+				#	(foo **)
+				#
+				} elsif ($op eq '&' or $op eq '-' or $op eq '*') {
+					if ($w2 and !$w1) {
+						print "need space before that '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+
+				# << and >> may either have or not have spaces both sides
+				} elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
+					 $op eq '^' or $op eq '|')
+				{
+					if ($s1 != $s2) {
+						print "need consistent spacing around '$op' $at\n";
+						print "$herecurr";
+						$clean = 0;
+					}
+
+				# All the others need spaces both sides.
+				} elsif (!$s1 or !$s2) {
+					print "need spaces around that '$op' $at\n";
+					print "$herecurr";
+					$clean = 0;
+				}
+			}
+		}
+
+#need space before brace following if, while, etc
+		if ($line=~/\(.*\){/) {
+			print "need a space before the brace\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+#goto labels aren't indented, allow a single space however
+		if ($line=~/^.\s+[A-Za-z\d_]+:/ and
+		   !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
+			print "labels should not be indented\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+# Need a space before open parenthesis after if, while etc
+		if ($line=~/(if|while|for|switch)\(/) {
+			print "need a space before the open parenthesis\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+# Check for illegal assignment in if conditional.
+		if ($line=~/(if|while)\s*\(.*[^<>!=]=[^=].*\)/) {
+			print "do not use assignment in if condition\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+
+		# Check for }<nl>else {, these must be at the same
+		# indent level to be relevant to each other.
+		if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
+						$previndent == $indent) {
+			print "else should follow close brace\n";
+			print "$hereprev";
+			$clean = 0;
+		}
+
+		# Check for switch () {<nl>case, these must be at the
+		# same indent.  We will only catch the first one, as our
+		# context is very small but people tend to be consistent
+		# so we will catch them out more often than not.
+		if ($prevline=~/\s*switch\s*\(.*\)/ and $line=~/\s*case\s+/
+						and $previndent != $indent) {
+			print "switch and case should be at the same indent\n";
+			print "$hereprev";
+			$clean = 0;
+		}
+
+#studly caps, commented out until figure out how to distinguish between use of existing and adding new
+#		if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
+#		    print "No studly caps, use _\n";
+#		    print "$herecurr";
+#		    $clean = 0;
+#		}
+
+#no spaces allowed after \ in define
+		if ($line=~/\#define.*\\\s$/) {
+			print("Whitepspace after \\ makes next lines useless\n");
+			print "$herecurr";
+			$clean = 0;
+		}
+
+#warn if <asm/foo.h> is #included and <linux/foo.h> is available.
+		if ($tree && $line =~ qr|\s*\#\s*include\s*\<asm\/(.*)\.h\>|) {
+			my $checkfile = "include/linux/$1.h";
+			if (-f $checkfile) {
+				print "Use #include <linux/$1.h> instead of <asm/$1.h>\n";
+				print $herecurr;
+				$clean = 0;
+			}
+		}
+
+#if/while/etc brace do not go on next line, unless #defining a do while loop, or if that brace on the next line is for something else
+		if ($prevline=~/(if|while|for|switch)\s*\(/) {
+			my @opened = $prevline=~/\(/g;
+			my @closed = $prevline=~/\)/g;
+			my $nr_line = $linenr;
+			my $remaining = $realcnt;
+			my $next_line = $line;
+			my $extra_lines = 0;
+			my $display_segment = $prevline;
+
+			while ($remaining > 0 && scalar @opened > scalar @closed) {
+				$prevline .= $next_line;
+				$display_segment .= "\n" . $next_line;
+				$next_line = $lines[$nr_line];
+				$nr_line++;
+				$remaining--;
+
+				@opened = $prevline=~/\(/g;
+				@closed = $prevline=~/\)/g;
+			}
+
+			if (($prevline=~/(if|while|for|switch)\s*\(.*\)\s*$/) and ($next_line=~/{/) and
+			   !($next_line=~/(if|while|for)/) and !($next_line=~/\#define.*do.*while/)) {
+				print "That { should be on the previous line\n";
+				print "$display_segment\n$next_line\n\n";
+				$clean = 0;
+			}
+		}
+
+#multiline macros should be enclosed in a do while loop
+		if (($prevline=~/\#define.*\\/) and !($prevline=~/do\s+{/) and
+		   !($prevline=~/\(\{/) and ($line=~/;\s*\\/) and
+		   !($line=~/do.*{/) and !($line=~/\(\{/)) {
+			print "Macros with multiple statements should be enclosed in a do - while loop\n";
+			print "$hereprev";
+			$clean = 0;
+		}
+
+# don't include deprecated include files
+		for my $inc (@deprecated) {
+			if ($line =~ m@\#\s*include\s*\<$inc>@) {
+				print "Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n";
+				print "$herecurr";
+				$clean = 0;
+			}
+		}
+
+# don't use kernel_thread()
+		if ($line =~ /\bkernel_thread\b/) {
+			print "Don't use kernel_thread(), use kthread(): see Documentation/feature-removal-schedule.txt\n";
+			print "$herecurr";
+			$clean = 0;
+		}
+	}
+
+	if ($chk_patch && !$is_patch) {
+		$clean = 0;
+		print "Does not appear to be a unified-diff format patch\n";
+	}
+	if ($is_patch && $chk_signoff && $signoff == 0) {
+		$clean = 0;
+		print "Missing Signed-off-by: line(s)\n";
+	}
+
+	if ($clean == 1 && $quiet == 0) {
+		print "Your patch has no obvious style problems and is ready for submission.\n"
+	}
+	if ($clean == 0 && $quiet == 0) {
+		print "Your patch has style problems, please review.  If any of these errors\n";
+		print "are false positives report them to the maintainer, see\n";
+		print "CHECKPATCH in MAINTAINERS.\n";
+	}
+	return $clean;
+}
...	...	@@ -84,4 +84,10 @@
84	84	24: Avoid whitespace damage such as indenting with spaces or whitespace
85	85	at the end of lines. You can test this by feeding the patch to
86	86	"git apply --check --whitespace=error-all"
	87	+
	88	+25: Check your patch for general style as detailed in
	89	+ Documentation/CodingStyle. Check for trivial violations with the
	90	+ patch style checker prior to submission (scripts/checkpatch.pl).
	91	+ You should be able to justify all violations that remain in
	92	+ your patch.
...	...	@@ -118,8 +118,21 @@
118	118
119	119
120	120
121		-4) Select e-mail destination.
	121	+4) Style check your changes.
122	122
	123	+Check your patch for basic style violations, details of which can be
	124	+found in Documentation/CodingStyle. Failure to do so simply wastes
	125	+the reviewers time and will get your patch rejected, probabally
	126	+without even being read.
	127	+
	128	+At a minimum you should check your patches with the patch style
	129	+checker prior to submission (scripts/patchcheck.pl). You should
	130	+be able to justify all violations that remain in your patch.
	131	+
	132	+
	133	+
	134	+5) Select e-mail destination.
	135	+
123	136	Look through the MAINTAINERS file and the source code, and determine
124	137	if your change applies to a specific subsystem of the kernel, with
125	138	an assigned maintainer. If so, e-mail that person.
...	...	@@ -146,7 +159,7 @@
146	159
147	160
148	161
149		-5) Select your CC (e-mail carbon copy) list.
	162	+6) Select your CC (e-mail carbon copy) list.
150	163
151	164	Unless you have a reason NOT to do so, CC linux-kernel@vger.kernel.org.
152	165
153	166
...	...	@@ -187,9 +200,8 @@
187	200
188	201
189	202
	203	+7) No MIME, no links, no compression, no attachments. Just plain text.
190	204
191		-6) No MIME, no links, no compression, no attachments. Just plain text.
192		-
193	205	Linus and other kernel developers need to be able to read and comment
194	206	on the changes you are submitting. It is important for a kernel
195	207	developer to be able to "quote" your changes, using standard e-mail
196	208
...	...	@@ -223,9 +235,9 @@
223	235
224	236
225	237
226		-7) E-mail size.
	238	+8) E-mail size.
227	239
228		-When sending patches to Linus, always follow step #6.
	240	+When sending patches to Linus, always follow step #7.
229	241
230	242	Large changes are not appropriate for mailing lists, and some
231	243	maintainers. If your patch, uncompressed, exceeds 40 kB in size,
...	...	@@ -234,7 +246,7 @@
234	246
235	247
236	248
237		-8) Name your kernel version.
	249	+9) Name your kernel version.
238	250
239	251	It is important to note, either in the subject line or in the patch
240	252	description, the kernel version to which this patch applies.
...	...	@@ -244,7 +256,7 @@
244	256
245	257
246	258
247		-9) Don't get discouraged. Re-submit.
	259	+10) Don't get discouraged. Re-submit.
248	260
249	261	After you have submitted your change, be patient and wait. If Linus
250	262	likes your change and applies it, it will appear in the next version
...	...	@@ -270,7 +282,7 @@
270	282
271	283
272	284
273		-10) Include PATCH in the subject
	285	+11) Include PATCH in the subject
274	286
275	287	Due to high e-mail traffic to Linus, and to linux-kernel, it is common
276	288	convention to prefix your subject line with [PATCH]. This lets Linus
...	...	@@ -279,7 +291,7 @@
279	291
280	292
281	293
282		-11) Sign your work
	294	+12) Sign your work
283	295
284	296	To improve tracking of who did what, especially with patches that can
285	297	percolate to their final resting place in the kernel through several
286	298
...	...	@@ -328,8 +340,9 @@
328	340	point out some special detail about the sign-off.
329	341
330	342
331		-12) The canonical patch format
332	343
	344	+13) The canonical patch format
	345	+
333	346	The canonical patch subject line is:
334	347
335	348	Subject: [PATCH 001/123] subsystem: summary phrase
...	...	@@ -426,6 +439,10 @@
426	439
427	440	Nuff said. If your code deviates too much from this, it is likely
428	441	to be rejected without further review, and without comment.
	442	+
	443	+Check your patches with the patch style checker prior to submission
	444	+(scripts/checkpatch.pl). You should be able to justify all
	445	+violations that remain in your patch.
429	446
430	447
431	448
...	...	@@ -70,6 +70,7 @@
70	70
71	71	What: Video4Linux API 1 ioctls and video_decoder.h from Video devices.
72	72	When: December 2006
	73	+Files: include/linux/video_decoder.h
73	74	Why: V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6
74	75	series. The old API have lots of drawbacks and don't provide enough
75	76	means to work with all video and audio standards. The newer API is
...	...	@@ -30,9 +30,12 @@
30	30	job the maintainers (and especially Linus) do is to keep things
31	31	looking the same. Sometimes this means that the clever hack in
32	32	your driver to get around a problem actually needs to become a
33		- generalized kernel feature ready for next time. See
34		- Documentation/CodingStyle for guidance here.
	33	+ generalized kernel feature ready for next time.
35	34
	35	+ PLEASE check your patch with the automated style checker
	36	+ (scripts/checkpatch.pl) to catch trival style violations.
	37	+ See Documentation/CodingStyle for guidance here.
	38	+
36	39	PLEASE try to include any credit lines you want added with the
37	40	patch. It avoids people being missed off by mistake and makes
38	41	it easier to know who wants adding and who doesn't.
...	...	@@ -971,6 +974,15 @@
971	974	M: johannes@sipsolutions.net
972	975	L: linux-wireless@vger.kernel.org
973	976	S: Maintained
	977	+
	978	+CHECKPATCH
	979	+P: Andy Whitcroft
	980	+M: apw@shadowen.org
	981	+P: Randy Dunlap
	982	+M: rdunlap@xenotime.net
	983	+P: Joel Schopp
	984	+M: jschopp@austin.ibm.com
	985	+S: Supported
974	986
975	987	COMMON INTERNET FILE SYSTEM (CIFS)
976	988	P: Steve French
	1	+#!/usr/bin/perl -w
	2	+# (c) 2001, Dave Jones. <davej@codemonkey.org.uk> (the file handling bit)
	3	+# (c) 2005, Joel Scohpp <jschopp@austin.ibm.com> (the ugly bit)
	4	+# (c) 2007, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite, etc)
	5	+# Licensed under the terms of the GNU GPL License version 2
	6	+
	7	+use strict;
	8	+
	9	+my $P = $0;
	10	+
	11	+my $V = '0.01';
	12	+
	13	+use Getopt::Long qw(:config no_auto_abbrev);
	14	+
	15	+my $quiet = 0;
	16	+my $tree = 1;
	17	+my $chk_signoff = 1;
	18	+my $chk_patch = 1;
	19	+GetOptions(
	20	+ 'q\|quiet' => \$quiet,
	21	+ 'tree!' => \$tree,
	22	+ 'signoff!' => \$chk_signoff,
	23	+ 'patch!' => \$chk_patch,
	24	+) or exit;
	25	+
	26	+my $exit = 0;
	27	+
	28	+if ($#ARGV < 0) {
	29	+ print "usage: patchstylecheckemail.pl [options] patchfile\n";
	30	+ print "version: $V\n";
	31	+ print "options: -q => quiet\n";
	32	+ print " --no-tree => run without a kernel tree\n";
	33	+ exit(1);
	34	+}
	35	+
	36	+if ($tree && !top_of_kernel_tree()) {
	37	+ print "Must be run from the top-level dir. of a kernel tree\n";
	38	+ exit(2);
	39	+}
	40	+
	41	+my @deprecated = ();
	42	+my $removal = 'Documentation/feature-removal-schedule.txt';
	43	+if ($tree && -f $removal) {
	44	+ open(REMOVE, "<$removal") \|\| die "$P: $removal: open failed - $!\n";
	45	+ while (<REMOVE>) {
	46	+ if (/^Files:\s+(.*\S)/) {
	47	+ for my $file (split(/[, ]+/, $1)) {
	48	+ if ($file =~ m@include/(.*)@) {
	49	+ push(@deprecated, $1);
	50	+ }
	51	+ }
	52	+ }
	53	+ }
	54	+}
	55	+
	56	+my @lines = ();
	57	+while (<>) {
	58	+ chomp;
	59	+ push(@lines, $_);
	60	+ if (eof(ARGV)) {
	61	+ if (!process($ARGV, @lines)) {
	62	+ $exit = 1;
	63	+ }
	64	+ @lines = ();
	65	+ }
	66	+}
	67	+
	68	+exit($exit);
	69	+
	70	+sub top_of_kernel_tree {
	71	+ if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
	72	+ (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
	73	+ (-d "Documentation") && (-d "arch") && (-d "include") &&
	74	+ (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
	75	+ (-d "kernel") && (-d "lib") && (-d "scripts")) {
	76	+ return 1;
	77	+ }
	78	+ return 0;
	79	+}
	80	+
	81	+sub expand_tabs {
	82	+ my ($str) = @_;
	83	+
	84	+ my $res = '';
	85	+ my $n = 0;
	86	+ for my $c (split(//, $str)) {
	87	+ if ($c eq "\t") {
	88	+ $res .= ' ';
	89	+ $n++;
	90	+ for (; ($n % 8) != 0; $n++) {
	91	+ $res .= ' ';
	92	+ }
	93	+ next;
	94	+ }
	95	+ $res .= $c;
	96	+ $n++;
	97	+ }
	98	+
	99	+ return $res;
	100	+}
	101	+
	102	+sub cat_vet {
	103	+ my ($vet) = @_;
	104	+
	105	+ $vet =~ s/\t/^I/;
	106	+ $vet =~ s/$/\$/;
	107	+
	108	+ return $vet;
	109	+}
	110	+
	111	+sub process {
	112	+ my $filename = shift;
	113	+ my @lines = @_;
	114	+
	115	+ my $linenr=0;
	116	+ my $prevline="";
	117	+ my $stashline="";
	118	+
	119	+ my $lineforcounting='';
	120	+ my $indent;
	121	+ my $previndent=0;
	122	+ my $stashindent=0;
	123	+
	124	+ my $clean = 1;
	125	+ my $signoff = 0;
	126	+ my $is_patch = 0;
	127	+
	128	+ # Trace the real file/line as we go.
	129	+ my $realfile = '';
	130	+ my $realline = 0;
	131	+ my $realcnt = 0;
	132	+ my $here = '';
	133	+ my $in_comment = 0;
	134	+ my $first_line = 0;
	135	+
	136	+ foreach my $line (@lines) {
	137	+ $linenr++;
	138	+
	139	+#extract the filename as it passes
	140	+ if ($line=~/^\+\+\+\s+(\S+)/) {
	141	+ $realfile=$1;
	142	+ $in_comment = 0;
	143	+ next;
	144	+ }
	145	+#extract the line range in the file after the patch is applied
	146	+ if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
	147	+ $is_patch = 1;
	148	+ $first_line = 1;
	149	+ $in_comment = 0;
	150	+ $realline=$1-1;
	151	+ if (defined $2) {
	152	+ $realcnt=$3+1;
	153	+ } else {
	154	+ $realcnt=1+1;
	155	+ }
	156	+ next;
	157	+ }
	158	+
	159	+#track the line number as we move through the hunk
	160	+ if ($line=~/^[ \+]/) {
	161	+ $realline++;
	162	+ $realcnt-- if ($realcnt != 0);
	163	+
	164	+ # track any sort of multi-line comment. Obviously if
	165	+ # the added text or context do not include the whole
	166	+ # comment we will not see it. Such is life.
	167	+ #
	168	+ # Guestimate if this is a continuing comment. If this
	169	+ # is the start of a diff block and this line starts
	170	+ # ' *' then it is very likely a comment.
	171	+ if ($first_line and $line =~ m@^.\s\@) {
	172	+ $in_comment = 1;
	173	+ }
	174	+ if ($line =~ m@/\*@) {
	175	+ $in_comment = 1;
	176	+ }
	177	+ if ($line =~ m@\*/@) {
	178	+ $in_comment = 0;
	179	+ }
	180	+
	181	+ $lineforcounting = $line;
	182	+ $lineforcounting =~ s/^\+//;
	183	+ $lineforcounting = expand_tabs($lineforcounting);
	184	+
	185	+ my ($white) = ($lineforcounting =~ /^(\s*)/);
	186	+ $indent = length($white);
	187	+
	188	+ # Track the previous line.
	189	+ ($prevline, $stashline) = ($stashline, $line);
	190	+ ($previndent, $stashindent) = ($stashindent, $indent);
	191	+ $first_line = 0;
	192	+ }
	193	+
	194	+#make up the handle for any error we report on this line
	195	+ $here = "PATCH: $ARGV:$linenr:";
	196	+ $here .= "\nFILE: $realfile:$realline:" if ($realcnt != 0);
	197	+
	198	+ my $herecurr = "$here\n$line\n\n";
	199	+ my $hereprev = "$here\n$prevline\n$line\n\n";
	200	+
	201	+#check the patch for a signoff:
	202	+ if ($line =~ /^\s*Signed-off-by:\s/) {
	203	+ $signoff++;
	204	+
	205	+ } elsif ($line =~ /^\s*signed-off-by:/i) {
	206	+ if (!($line =~ /^\s*Signed-off-by:/)) {
	207	+ print "use Signed-off-by:\n";
	208	+ print "$herecurr";
	209	+ $clean = 0;
	210	+ }
	211	+ if ($line =~ /^\s*signed-off-by:\S/i) {
	212	+ print "need space after Signed-off-by:\n";
	213	+ print "$herecurr";
	214	+ $clean = 0;
	215	+ }
	216	+ }
	217	+
	218	+#ignore lines not being added
	219	+ if ($line=~/^[^\+]/) {next;}
	220	+
	221	+# check we are in a valid source file *.[hcsS] if not then ignore this hunk
	222	+ next if ($realfile !~ /\.[hcsS]$/);
	223	+
	224	+#trailing whitespace
	225	+ if ($line=~/\S\s+$/) {
	226	+ my $herevet = "$here\n" . cat_vet($line) . "\n\n";
	227	+ print "trailing whitespace\n";
	228	+ print "$herevet";
	229	+ $clean = 0;
	230	+ }
	231	+#80 column limit
	232	+ if (!($prevline=~/\/\\/) && length($lineforcounting) > 80) {
	233	+ print "line over 80 characters\n";
	234	+ print "$herecurr";
	235	+ $clean = 0;
	236	+ }
	237	+
	238	+# check we are in a valid source file *.[hc] if not then ignore this hunk
	239	+ next if ($realfile !~ /\.[hc]$/);
	240	+
	241	+# at the beginning of a line any tabs must come first and anything
	242	+# more than 8 must use tabs.
	243	+ if ($line=~/^\+\s* \t\s\S/ or $line=~/^\+\s \s*/) {
	244	+ my $herevet = "$here\n" . cat_vet($line) . "\n\n";
	245	+ print "use tabs not spaces\n";
	246	+ print "$herevet";
	247	+ $clean = 0;
	248	+ }
	249	+
	250	+ #
	251	+ # The rest of our checks refer specifically to C style
	252	+ # only apply those _outside_ comments.
	253	+ #
	254	+ next if ($in_comment);
	255	+
	256	+# no C99 // comments
	257	+ if ($line =~ m@//@ and !($line =~ m@\".//.\"@)) {
	258	+ print "do not use C99 // comments\n";
	259	+ print "$herecurr";
	260	+ $clean = 0;
	261	+ }
	262	+
	263	+ # Remove comments from the line before processing.
	264	+ $line =~ s@/\.\*/@@g;
	265	+ $line =~ s@/\.@@;
	266	+ $line =~ s@.\/@@;
	267	+ $line =~ s@//.*@@;
	268	+
	269	+#EXPORT_SYMBOL should immediately follow its function closing }.
	270	+ if (($line =~ /EXPORT_SYMBOL.\(.\)/) \|\|
	271	+ ($line =~ /EXPORT_UNUSED_SYMBOL.\(.\)/)) {
	272	+ if (($prevline !~ /^}/) &&
	273	+ ($prevline !~ /^\+}/) &&
	274	+ ($prevline !~ /^ }/)) {
	275	+ print "EXPORT_SYMBOL(func); should immediately follow its function\n";
	276	+ print "$herecurr";
	277	+ $clean = 0;
	278	+ }
	279	+ }
	280	+
	281	+ # check for static initialisers.
	282	+ if ($line=~/\sstatic\s.=\s+(0\|NULL);/) {
	283	+ print "do not initialise statics to 0 or NULL\n";
	284	+ print "$herecurr";
	285	+ $clean = 0;
	286	+ }
	287	+
	288	+ # check for new typedefs.
	289	+ if ($line=~/\s*typedef\s/) {
	290	+ print "do not add new typedefs\n";
	291	+ print "$herecurr";
	292	+ $clean = 0;
	293	+ }
	294	+
	295	+# * goes on variable not on type
	296	+ if ($line=~/[A-Za-z\d_]+\* [A-Za-z\d_]+/) {
	297	+ print "\"foo* bar\" should be \"foo *bar\"\n";
	298	+ print "$herecurr";
	299	+ $clean = 0;
	300	+ }
	301	+
	302	+# # no BUG() or BUG_ON()
	303	+# if ($line =~ /\b(BUG\|BUG_ON)\b/) {
	304	+# print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
	305	+# print "$herecurr";
	306	+# $clean = 0;
	307	+# }
	308	+
	309	+# printk should use KERN_* levels
	310	+ if ($line =~ /\bprintk\((?!KERN_)/) {
	311	+ print "printk() should include KERN_ facility level\n";
	312	+ print "$herecurr";
	313	+ $clean = 0;
	314	+ }
	315	+
	316	+#function brace can't be on same line, except for #defines of do while, or if closed on same line
	317	+ if (($line=~/[A-Za-z\d_]+\\s+\[A-Za-z\d_]+\(.\). {/) and
	318	+ !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
	319	+ print "braces following function declarations go on the next line\n";
	320	+ print "$herecurr";
	321	+ $clean = 0;
	322	+ }
	323	+ my $opline = $line;
	324	+ $opline =~ s/^.//;
	325	+ if (!($line=~/\#\s*include/)) {
	326	+ # Check operator spacing.
	327	+ my @elements = split(/(<<=\|>>=\|<=\|>=\|==\|!=\|\+=\|-=\|\=\|\/=\|%=\|\^=\|\\|=\|&=\|->\|<<\|>>\|<\|>\|=\|!\|~\|&&\|\\|\\|\|,\|\^\|\+\+\|--\|;\|&\|\\|\|\+\|-\|\\|\/\/\|\/)/, $opline);
	328	+ for (my $n = 0; $n < $#elements; $n += 2) {
	329	+ # $wN says we have white-space before or after
	330	+ # $sN says we have a separator before or after
	331	+ # $oN says we have another operator before or after
	332	+ my $w1 = $elements[$n] =~ /\s$/;
	333	+ my $s1 = $elements[$n] =~ /(\[\|\(\|\s)$/;
	334	+ my $o1 = $elements[$n] eq '';
	335	+ my $op = $elements[$n + 1];
	336	+ my $w2 = 1;
	337	+ my $s2 = 1;
	338	+ my $o2 = 0;
	339	+ # If we have something after the operator handle it.
	340	+ if (defined $elements[$n + 2]) {
	341	+ $w2 = $elements[$n + 2] =~ /^\s/;
	342	+ $s2 = $elements[$n + 2] =~ /^(\s\|\)\|\]\|;)/;
	343	+ $o2 = $elements[$n + 2] eq '';
	344	+ }
	345	+
	346	+ # Generate the context.
	347	+ my $at = "here: ";
	348	+ for (my $m = $n; $m >= 0; $m--) {
	349	+ if ($elements[$m] ne '') {
	350	+ $at .= $elements[$m];
	351	+ last;
	352	+ }
	353	+ }
	354	+ $at .= $op;
	355	+ for (my $m = $n + 2; defined $elements[$m]; $m++) {
	356	+ if ($elements[$m] ne '') {
	357	+ $at .= $elements[$m];
	358	+ last;
	359	+ }
	360	+ }
	361	+
	362	+ ##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
	363	+ # Skip things apparently in quotes.
	364	+ next if ($line=~/\".\Q$op\E.\"/ or $line=~/\'\Q$op\E\'/);
	365	+
	366	+ # We need ; as an operator. // is a comment.
	367	+ if ($op eq ';' or $op eq '//') {
	368	+
	369	+ # -> should have no spaces
	370	+ } elsif ($op eq '->') {
	371	+ if ($s1 or $s2) {
	372	+ print "no spaces around that '$op' $at\n";
	373	+ print "$herecurr";
	374	+ $clean = 0;
	375	+ }
	376	+
	377	+ # , must have a space on the right.
	378	+ } elsif ($op eq ',') {
	379	+ if (!$s2) {
	380	+ print "need space after that '$op' $at\n";
	381	+ print "$herecurr";
	382	+ $clean = 0;
	383	+ }
	384	+
	385	+ # unary ! and unary ~ are allowed no space on the right
	386	+ } elsif ($op eq '!' or $op eq '~') {
	387	+ if (!$s1 && !$o1) {
	388	+ print "need space before that '$op' $at\n";
	389	+ print "$herecurr";
	390	+ $clean = 0;
	391	+ }
	392	+ if ($s2) {
	393	+ print "no space after that '$op' $at\n";
	394	+ print "$herecurr";
	395	+ $clean = 0;
	396	+ }
	397	+
	398	+ # unary ++ and unary -- are allowed no space on one side.
	399	+ } elsif ($op eq '++' or $op eq '--') {
	400	+ if (($s1 && $s2) \|\| ((!$s1 && !$o1) && (!$s2 && !$o2))) {
	401	+ print "need space one side of that '$op' $at\n";
	402	+ print "$herecurr";
	403	+ $clean = 0;
	404	+ }
	405	+
	406	+ # & is both unary and binary
	407	+ # unary:
	408	+ # a &b
	409	+ # binary (consistent spacing):
	410	+ # a&b OK
	411	+ # a & b OK
	412	+ #
	413	+ # boiling down to: if there is a space on the right then there
	414	+ # should be one on the left.
	415	+ #
	416	+ # - is the same
	417	+ #
	418	+ # * is the same only adding:
	419	+ # type:
	420	+ # (foo *)
	421	+ # (foo **)
	422	+ #
	423	+ } elsif ($op eq '&' or $op eq '-' or $op eq '*') {
	424	+ if ($w2 and !$w1) {
	425	+ print "need space before that '$op' $at\n";
	426	+ print "$herecurr";
	427	+ $clean = 0;
	428	+ }
	429	+
	430	+ # << and >> may either have or not have spaces both sides
	431	+ } elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
	432	+ $op eq '^' or $op eq '\|')
	433	+ {
	434	+ if ($s1 != $s2) {
	435	+ print "need consistent spacing around '$op' $at\n";
	436	+ print "$herecurr";
	437	+ $clean = 0;
	438	+ }
	439	+
	440	+ # All the others need spaces both sides.
	441	+ } elsif (!$s1 or !$s2) {
	442	+ print "need spaces around that '$op' $at\n";
	443	+ print "$herecurr";
	444	+ $clean = 0;
	445	+ }
	446	+ }
	447	+ }
	448	+
	449	+#need space before brace following if, while, etc
	450	+ if ($line=~/\(.*\){/) {
	451	+ print "need a space before the brace\n";
	452	+ print "$herecurr";
	453	+ $clean = 0;
	454	+ }
	455	+
	456	+#goto labels aren't indented, allow a single space however
	457	+ if ($line=~/^.\s+[A-Za-z\d_]+:/ and
	458	+ !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
	459	+ print "labels should not be indented\n";
	460	+ print "$herecurr";
	461	+ $clean = 0;
	462	+ }
	463	+
	464	+# Need a space before open parenthesis after if, while etc
	465	+ if ($line=~/(if\|while\|for\|switch)\(/) {
	466	+ print "need a space before the open parenthesis\n";
	467	+ print "$herecurr";
	468	+ $clean = 0;
	469	+ }
	470	+
	471	+# Check for illegal assignment in if conditional.
	472	+ if ($line=~/(if\|while)\s\(.[^<>!=]=[^=].*\)/) {
	473	+ print "do not use assignment in if condition\n";
	474	+ print "$herecurr";
	475	+ $clean = 0;
	476	+ }
	477	+
	478	+ # Check for }<nl>else {, these must be at the same
	479	+ # indent level to be relevant to each other.
	480	+ if ($prevline=~/}\s$/ and $line=~/^.\selse\s*/ and
	481	+ $previndent == $indent) {
	482	+ print "else should follow close brace\n";
	483	+ print "$hereprev";
	484	+ $clean = 0;
	485	+ }
	486	+
	487	+ # Check for switch () {<nl>case, these must be at the
	488	+ # same indent. We will only catch the first one, as our
	489	+ # context is very small but people tend to be consistent
	490	+ # so we will catch them out more often than not.
	491	+ if ($prevline=~/\sswitch\s\(.\)/ and $line=~/\scase\s+/
	492	+ and $previndent != $indent) {
	493	+ print "switch and case should be at the same indent\n";
	494	+ print "$hereprev";
	495	+ $clean = 0;
	496	+ }
	497	+
	498	+#studly caps, commented out until figure out how to distinguish between use of existing and adding new
	499	+# if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
	500	+# print "No studly caps, use _\n";
	501	+# print "$herecurr";
	502	+# $clean = 0;
	503	+# }
	504	+
	505	+#no spaces allowed after \ in define
	506	+ if ($line=~/\#define.*\\\s$/) {
	507	+ print("Whitepspace after \\ makes next lines useless\n");
	508	+ print "$herecurr";
	509	+ $clean = 0;
	510	+ }
	511	+
	512	+#warn if <asm/foo.h> is #included and <linux/foo.h> is available.
	513	+ if ($tree && $line =~ qr\|\s\#\sinclude\s\<asm\/(.)\.h\>\|) {
	514	+ my $checkfile = "include/linux/$1.h";
	515	+ if (-f $checkfile) {
	516	+ print "Use #include <linux/$1.h> instead of <asm/$1.h>\n";
	517	+ print $herecurr;
	518	+ $clean = 0;
	519	+ }
	520	+ }
	521	+
	522	+#if/while/etc brace do not go on next line, unless #defining a do while loop, or if that brace on the next line is for something else
	523	+ if ($prevline=~/(if\|while\|for\|switch)\s*\(/) {
	524	+ my @opened = $prevline=~/\(/g;
	525	+ my @closed = $prevline=~/\)/g;
	526	+ my $nr_line = $linenr;
	527	+ my $remaining = $realcnt;
	528	+ my $next_line = $line;
	529	+ my $extra_lines = 0;
	530	+ my $display_segment = $prevline;
	531	+
	532	+ while ($remaining > 0 && scalar @opened > scalar @closed) {
	533	+ $prevline .= $next_line;
	534	+ $display_segment .= "\n" . $next_line;
	535	+ $next_line = $lines[$nr_line];
	536	+ $nr_line++;
	537	+ $remaining--;
	538	+
	539	+ @opened = $prevline=~/\(/g;
	540	+ @closed = $prevline=~/\)/g;
	541	+ }
	542	+
	543	+ if (($prevline=~/(if\|while\|for\|switch)\s\(.\)\s*$/) and ($next_line=~/{/) and
	544	+ !($next_line=~/(if\|while\|for)/) and !($next_line=~/\#define.do.while/)) {
	545	+ print "That { should be on the previous line\n";
	546	+ print "$display_segment\n$next_line\n\n";
	547	+ $clean = 0;
	548	+ }
	549	+ }
	550	+
	551	+#multiline macros should be enclosed in a do while loop
	552	+ if (($prevline=~/\#define.*\\/) and !($prevline=~/do\s+{/) and
	553	+ !($prevline=~/\(\{/) and ($line=~/;\s*\\/) and
	554	+ !($line=~/do.*{/) and !($line=~/\(\{/)) {
	555	+ print "Macros with multiple statements should be enclosed in a do - while loop\n";
	556	+ print "$hereprev";
	557	+ $clean = 0;
	558	+ }
	559	+
	560	+# don't include deprecated include files
	561	+ for my $inc (@deprecated) {
	562	+ if ($line =~ m@\#\sinclude\s\<$inc>@) {
	563	+ print "Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n";
	564	+ print "$herecurr";
	565	+ $clean = 0;
	566	+ }
	567	+ }
	568	+
	569	+# don't use kernel_thread()
	570	+ if ($line =~ /\bkernel_thread\b/) {
	571	+ print "Don't use kernel_thread(), use kthread(): see Documentation/feature-removal-schedule.txt\n";
	572	+ print "$herecurr";
	573	+ $clean = 0;
	574	+ }
	575	+ }
	576	+
	577	+ if ($chk_patch && !$is_patch) {
	578	+ $clean = 0;
	579	+ print "Does not appear to be a unified-diff format patch\n";
	580	+ }
	581	+ if ($is_patch && $chk_signoff && $signoff == 0) {
	582	+ $clean = 0;
	583	+ print "Missing Signed-off-by: line(s)\n";
	584	+ }
	585	+
	586	+ if ($clean == 1 && $quiet == 0) {
	587	+ print "Your patch has no obvious style problems and is ready for submission.\n"
	588	+ }
	589	+ if ($clean == 0 && $quiet == 0) {
	590	+ print "Your patch has style problems, please review. If any of these errors\n";
	591	+ print "are false positives report them to the maintainer, see\n";
	592	+ print "CHECKPATCH in MAINTAINERS.\n";
	593	+ }
	594	+ return $clean;
	595	+}