checkpatch.pl

				next if ($f =~ /^-/);

				if ($lines[$ln - 1] =~ /.\s*(?:bool|tristate)\s*\"/) {
					$is_start = 1;
				} elsif ($lines[$ln - 1] =~ /.\s*(?:---)?help(?:---)?$/) {
					$length = -1;
				}

				$f =~ s/^.//;
				$f =~ s/#.*//;
				$f =~ s/^\s+//;
				next if ($f =~ /^$/);
				if ($f =~ /^\s*config\s/) {
					$is_end = 1;
					last;
				}
				$length++;
			}
			WARN("CONFIG_DESCRIPTION",
			     "please write a paragraph that describes the config symbol fully\n" . $herecurr) if ($is_start && $is_end && $length < 4);
			#print "is_start<$is_start> is_end<$is_end> length<$length>\n";
		}

# discourage the addition of CONFIG_EXPERIMENTAL in Kconfig.
		if ($realfile =~ /Kconfig/ &&
		    $line =~ /.\s*depends on\s+.*\bEXPERIMENTAL\b/) {
			WARN("CONFIG_EXPERIMENTAL",
			     "Use of CONFIG_EXPERIMENTAL is deprecated. For alternatives, see https://lkml.org/lkml/2012/10/23/580\n");
		}

		if (($realfile =~ /Makefile.*/ || $realfile =~ /Kbuild.*/) &&
		    ($line =~ /\+(EXTRA_[A-Z]+FLAGS).*/)) {
			my $flag = $1;
			my $replacement = {
				'EXTRA_AFLAGS' =>   'asflags-y',
				'EXTRA_CFLAGS' =>   'ccflags-y',
				'EXTRA_CPPFLAGS' => 'cppflags-y',
				'EXTRA_LDFLAGS' =>  'ldflags-y',
			};

			WARN("DEPRECATED_VARIABLE",
			     "Use of $flag is deprecated, please use \`$replacement->{$flag} instead.\n" . $herecurr) if ($replacement->{$flag});
		}

# check for DT compatible documentation
		if (defined $root && $realfile =~ /\.dts/ &&
		    $rawline =~ /^\+\s*compatible\s*=/) {
			my @compats = $rawline =~ /\"([a-zA-Z0-9\-\,\.\+_]+)\"/g;

			foreach my $compat (@compats) {
				my $compat2 = $compat;
				my $dt_path =  $root . "/Documentation/devicetree/bindings/";
				$compat2 =~ s/\,[a-z]*\-/\,<\.\*>\-/;
				`grep -Erq "$compat|$compat2" $dt_path`;
				if ( $? >> 8 ) {
					WARN("UNDOCUMENTED_DT_STRING",
					     "DT compatible string \"$compat\" appears un-documented -- check $dt_path\n" . $herecurr);
				}

				my $vendor = $compat;
				my $vendor_path = $dt_path . "vendor-prefixes.txt";
				next if (! -f $vendor_path);
				$vendor =~ s/^([a-zA-Z0-9]+)\,.*/$1/;
				`grep -Eq "$vendor" $vendor_path`;
				if ( $? >> 8 ) {
					WARN("UNDOCUMENTED_DT_STRING",
					     "DT compatible string vendor \"$vendor\" appears un-documented -- check $vendor_path\n" . $herecurr);
				}
			}
		}

# check we are in a valid source file if not then ignore this hunk
		next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);

#line length limit
		if ($line =~ /^\+/ && $prevrawline !~ /\/\*\*/ &&
		    $rawline !~ /^.\s*\*\s*\@$Ident\s/ &&
		    !($line =~ /^\+\s*$logFunctions\s*\(\s*(?:(KERN_\S+\s*|[^"]*))?"[X\t]*"\s*(?:|,|\)\s*;)\s*$/ ||
		    $line =~ /^\+\s*"[^"]*"\s*(?:\s*|,|\)\s*;)\s*$/) &&
		    $length > $max_line_length)
		{
			WARN("LONG_LINE",
			     "line over $max_line_length characters\n" . $herecurr);
		}

# Check for user-visible strings broken across lines, which breaks the ability
# to grep for the string.  Make exceptions when the previous string ends in a
# newline (multiple lines in one string constant) or '\t', '\r', ';', or '{'
# (common in inline assembly) or is a octal \123 or hexadecimal \xaf value
		if ($line =~ /^\+\s*"/ &&
		    $prevline =~ /"\s*$/ &&
		    $prevrawline !~ /(?:\\(?:[ntr]|[0-7]{1,3}|x[0-9a-fA-F]{1,2})|;\s*|\{\s*)"\s*$/) {
			WARN("SPLIT_STRING",
			     "quoted string split across lines\n" . $hereprev);
		}

# check for spaces before a quoted newline
		if ($rawline =~ /^.*\".*\s\\n/) {
			if (WARN("QUOTED_WHITESPACE_BEFORE_NEWLINE",
				 "unnecessary whitespace before a quoted newline\n" . $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/^(\+.*\".*)\s+\\n/$1\\n/;
			}

		}

# check for adding lines without a newline.
		if ($line =~ /^\+/ && defined $lines[$linenr] && $lines[$linenr] =~ /^\\ No newline at end of file/) {
			WARN("MISSING_EOF_NEWLINE",
			     "adding a line without newline at end of file\n" . $herecurr);
		}

# Blackfin: use hi/lo macros
		if ($realfile =~ m@arch/blackfin/.*\.S$@) {
			if ($line =~ /\.[lL][[:space:]]*=.*&[[:space:]]*0x[fF][fF][fF][fF]/) {
				my $herevet = "$here\n" . cat_vet($line) . "\n";
				ERROR("LO_MACRO",
				      "use the LO() macro, not (... & 0xFFFF)\n" . $herevet);
			}
			if ($line =~ /\.[hH][[:space:]]*=.*>>[[:space:]]*16/) {
				my $herevet = "$here\n" . cat_vet($line) . "\n";
				ERROR("HI_MACRO",
				      "use the HI() macro, not (... >> 16)\n" . $herevet);
			}
		}

# check we are in a valid source file C or perl if not then ignore this hunk
		next if ($realfile !~ /\.(h|c|pl)$/);

# at the beginning of a line any tabs must come first and anything
# more than 8 must use tabs.
		if ($rawline =~ /^\+\s* \t\s*\S/ ||
		    $rawline =~ /^\+\s*        \s*/) {
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			$rpt_cleaners = 1;
			if (ERROR("CODE_INDENT",
				  "code indent should use tabs where possible\n" . $herevet) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/^\+([ \t]+)/"\+" . tabify($1)/e;
			}
		}

# check for space before tabs.
		if ($rawline =~ /^\+/ && $rawline =~ / \t/) {
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			if (WARN("SPACE_BEFORE_TAB",
				"please, no space before tabs\n" . $herevet) &&
			    $fix) {
				while ($fixed[$linenr - 1] =~
					   s/(^\+.*) {8,8}\t/$1\t\t/) {}
				while ($fixed[$linenr - 1] =~
					   s/(^\+.*) +\t/$1\t/) {}
			}
		}

# check for && or || at the start of a line
		if ($rawline =~ /^\+\s*(&&|\|\|)/) {
			CHK("LOGICAL_CONTINUATIONS",
			    "Logical continuations should be on the previous line\n" . $hereprev);
		}

# check multi-line statement indentation matches previous line
		if ($^V && $^V ge 5.10.0 &&
		    $prevline =~ /^\+(\t*)(if \(|$Ident\().*(\&\&|\|\||,)\s*$/) {
			$prevline =~ /^\+(\t*)(.*)$/;
			my $oldindent = $1;
			my $rest = $2;

			my $pos = pos_last_openparen($rest);
			if ($pos >= 0) {
				$line =~ /^(\+| )([ \t]*)/;
				my $newindent = $2;

				my $goodtabindent = $oldindent .
					"\t" x ($pos / 8) .
					" "  x ($pos % 8);
				my $goodspaceindent = $oldindent . " "  x $pos;

				if ($newindent ne $goodtabindent &&
				    $newindent ne $goodspaceindent) {

					if (CHK("PARENTHESIS_ALIGNMENT",
						"Alignment should match open parenthesis\n" . $hereprev) &&
					    $fix && $line =~ /^\+/) {
						$fixed[$linenr - 1] =~
						    s/^\+[ \t]*/\+$goodtabindent/;
					}
				}
			}
		}

		if ($line =~ /^\+.*\*[ \t]*\)[ \t]+(?!$Assignment|$Arithmetic)/) {
			if (CHK("SPACING",
				"No space is necessary after a cast\n" . $hereprev) &&
			    $fix) {
				$fixed[$linenr - 1] =~
				    s/^(\+.*\*[ \t]*\))[ \t]+/$1/;
			}
		}

		if ($realfile =~ m@^(drivers/net/|net/)@ &&
		    $prevrawline =~ /^\+[ \t]*\/\*[ \t]*$/ &&
		    $rawline =~ /^\+[ \t]*\*/) {
			WARN("NETWORKING_BLOCK_COMMENT_STYLE",
			     "networking block comments don't use an empty /* line, use /* Comment...\n" . $hereprev);
		}

		if ($realfile =~ m@^(drivers/net/|net/)@ &&
		    $prevrawline =~ /^\+[ \t]*\/\*/ &&		#starting /*
		    $prevrawline !~ /\*\/[ \t]*$/ &&		#no trailing */
		    $rawline =~ /^\+/ &&			#line is new
		    $rawline !~ /^\+[ \t]*\*/) {		#no leading *
			WARN("NETWORKING_BLOCK_COMMENT_STYLE",
			     "networking block comments start with * on subsequent lines\n" . $hereprev);
		}

		if ($realfile =~ m@^(drivers/net/|net/)@ &&
		    $rawline !~ m@^\+[ \t]*\*/[ \t]*$@ &&	#trailing */
		    $rawline !~ m@^\+.*/\*.*\*/[ \t]*$@ &&	#inline /*...*/
		    $rawline !~ m@^\+.*\*{2,}/[ \t]*$@ &&	#trailing **/
		    $rawline =~ m@^\+[ \t]*.+\*\/[ \t]*$@) {	#non blank */
			WARN("NETWORKING_BLOCK_COMMENT_STYLE",
			     "networking block comments put the trailing */ on a separate line\n" . $herecurr);
		}

# check for spaces at the beginning of a line.
# Exceptions:
#  1) within comments
#  2) indented preprocessor commands
#  3) hanging labels
		if ($rawline =~ /^\+ / && $line !~ /^\+ *(?:$;|#|$Ident:)/)  {
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			if (WARN("LEADING_SPACE",
				 "please, no spaces at the start of a line\n" . $herevet) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/^\+([ \t]+)/"\+" . tabify($1)/e;
			}
		}

# check we are in a valid C source file if not then ignore this hunk
		next if ($realfile !~ /\.(h|c)$/);

# discourage the addition of CONFIG_EXPERIMENTAL in #if(def).
		if ($line =~ /^\+\s*\#\s*if.*\bCONFIG_EXPERIMENTAL\b/) {
			WARN("CONFIG_EXPERIMENTAL",
			     "Use of CONFIG_EXPERIMENTAL is deprecated. For alternatives, see https://lkml.org/lkml/2012/10/23/580\n");
		}

# check for RCS/CVS revision markers
		if ($rawline =~ /^\+.*\$(Revision|Log|Id)(?:\$|)/) {
			WARN("CVS_KEYWORD",
			     "CVS style keyword markers, these will _not_ be updated\n". $herecurr);
		}

# Blackfin: don't use __builtin_bfin_[cs]sync
		if ($line =~ /__builtin_bfin_csync/) {
			my $herevet = "$here\n" . cat_vet($line) . "\n";
			ERROR("CSYNC",
			      "use the CSYNC() macro in asm/blackfin.h\n" . $herevet);
		}
		if ($line =~ /__builtin_bfin_ssync/) {
			my $herevet = "$here\n" . cat_vet($line) . "\n";
			ERROR("SSYNC",
			      "use the SSYNC() macro in asm/blackfin.h\n" . $herevet);
		}

# check for old HOTPLUG __dev<foo> section markings
		if ($line =~ /\b(__dev(init|exit)(data|const|))\b/) {
			WARN("HOTPLUG_SECTION",
			     "Using $1 is unnecessary\n" . $herecurr);
		}

# Check for potential 'bare' types
		my ($stat, $cond, $line_nr_next, $remain_next, $off_next,
		    $realline_next);
#print "LINE<$line>\n";
		if ($linenr >= $suppress_statement &&
		    $realcnt && $sline =~ /.\s*\S/) {
			($stat, $cond, $line_nr_next, $remain_next, $off_next) =
				ctx_statement_block($linenr, $realcnt, 0);
			$stat =~ s/\n./\n /g;
			$cond =~ s/\n./\n /g;

#print "linenr<$linenr> <$stat>\n";
			# If this statement has no statement boundaries within
			# it there is no point in retrying a statement scan
			# until we hit end of it.
			my $frag = $stat; $frag =~ s/;+\s*$//;
			if ($frag !~ /(?:{|;)/) {
#print "skip<$line_nr_next>\n";
				$suppress_statement = $line_nr_next;
			}

			# Find the real next line.
			$realline_next = $line_nr_next;
			if (defined $realline_next &&
			    (!defined $lines[$realline_next - 1] ||
			     substr($lines[$realline_next - 1], $off_next) =~ /^\s*$/)) {
				$realline_next++;
			}

			my $s = $stat;
			$s =~ s/{.*$//s;

			# Ignore goto labels.
			if ($s =~ /$Ident:\*$/s) {

			# Ignore functions being called
			} elsif ($s =~ /^.\s*$Ident\s*\(/s) {

			} elsif ($s =~ /^.\s*else\b/s) {

			# declarations always start with types
			} elsif ($prev_values eq 'E' && $s =~ /^.\s*(?:$Storage\s+)?(?:$Inline\s+)?(?:const\s+)?((?:\s*$Ident)+?)\b(?:\s+$Sparse)?\s*\**\s*(?:$Ident|\(\*[^\)]*\))(?:\s*$Modifier)?\s*(?:;|=|,|\()/s) {
				my $type = $1;
				$type =~ s/\s+/ /g;
				possible($type, "A:" . $s);

			# definitions in global scope can only start with types
			} elsif ($s =~ /^.(?:$Storage\s+)?(?:$Inline\s+)?(?:const\s+)?($Ident)\b\s*(?!:)/s) {
				possible($1, "B:" . $s);
			}

			# any (foo ... *) is a pointer cast, and foo is a type
			while ($s =~ /\(($Ident)(?:\s+$Sparse)*[\s\*]+\s*\)/sg) {
				possible($1, "C:" . $s);
			}

			# Check for any sort of function declaration.
			# int foo(something bar, other baz);
			# void (*store_gdt)(x86_descr_ptr *);
			if ($prev_values eq 'E' && $s =~ /^(.(?:typedef\s*)?(?:(?:$Storage|$Inline)\s*)*\s*$Type\s*(?:\b$Ident|\(\*\s*$Ident\))\s*)\(/s) {
				my ($name_len) = length($1);

				my $ctx = $s;
				substr($ctx, 0, $name_len + 1, '');
				$ctx =~ s/\)[^\)]*$//;

				for my $arg (split(/\s*,\s*/, $ctx)) {
					if ($arg =~ /^(?:const\s+)?($Ident)(?:\s+$Sparse)*\s*\**\s*(:?\b$Ident)?$/s || $arg =~ /^($Ident)$/s) {

						possible($1, "D:" . $s);
					}
				}
			}

		}

#
# Checks which may be anchored in the context.
#

# Check for switch () and associated case and default
# statements should be at the same indent.
		if ($line=~/\bswitch\s*\(.*\)/) {
			my $err = '';
			my $sep = '';
			my @ctx = ctx_block_outer($linenr, $realcnt);
			shift(@ctx);
			for my $ctx (@ctx) {
				my ($clen, $cindent) = line_stats($ctx);
				if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
							$indent != $cindent) {
					$err .= "$sep$ctx\n";
					$sep = '';
				} else {
					$sep = "[...]\n";
				}
			}
			if ($err ne '') {
				ERROR("SWITCH_CASE_INDENT_LEVEL",
				      "switch and case should be at the same indent\n$hereline$err");
			}
		}

# 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 ($line =~ /(.*)\b((?:if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.\s*\#/) {
			my $pre_ctx = "$1$2";

			my ($level, @ctx) = ctx_statement_level($linenr, $realcnt, 0);

			if ($line =~ /^\+\t{6,}/) {
				WARN("DEEP_INDENTATION",
				     "Too many leading tabs - consider code refactoring\n" . $herecurr);
			}

			my $ctx_cnt = $realcnt - $#ctx - 1;
			my $ctx = join("\n", @ctx);

			my $ctx_ln = $linenr;
			my $ctx_skip = $realcnt;

			while ($ctx_skip > $ctx_cnt || ($ctx_skip == $ctx_cnt &&
					defined $lines[$ctx_ln - 1] &&
					$lines[$ctx_ln - 1] =~ /^-/)) {
				##print "SKIP<$ctx_skip> CNT<$ctx_cnt>\n";
				$ctx_skip-- if (!defined $lines[$ctx_ln - 1] || $lines[$ctx_ln - 1] !~ /^-/);
				$ctx_ln++;
			}

			#print "realcnt<$realcnt> ctx_cnt<$ctx_cnt>\n";
			#print "pre<$pre_ctx>\nline<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>\n";

			if ($ctx !~ /{\s*/ && defined($lines[$ctx_ln -1]) && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
				ERROR("OPEN_BRACE",
				      "that open brace { should be on the previous line\n" .
					"$here\n$ctx\n$rawlines[$ctx_ln - 1]\n");
			}
			if ($level == 0 && $pre_ctx !~ /}\s*while\s*\($/ &&
			    $ctx =~ /\)\s*\;\s*$/ &&
			    defined $lines[$ctx_ln - 1])
			{
				my ($nlength, $nindent) = line_stats($lines[$ctx_ln - 1]);
				if ($nindent > $indent) {
					WARN("TRAILING_SEMICOLON",
					     "trailing semicolon indicates no statements, indent implies otherwise\n" .
						"$here\n$ctx\n$rawlines[$ctx_ln - 1]\n");
				}
			}
		}

# Check relative indent for conditionals and blocks.
		if ($line =~ /\b(?:(?:if|while|for)\s*\(|do\b)/ && $line !~ /^.\s*#/ && $line !~ /\}\s*while\s*/) {
			($stat, $cond, $line_nr_next, $remain_next, $off_next) =
				ctx_statement_block($linenr, $realcnt, 0)
					if (!defined $stat);
			my ($s, $c) = ($stat, $cond);

			substr($s, 0, length($c), '');

			# Make sure we remove the line prefixes as we have
			# none on the first line, and are going to readd them
			# where necessary.
			$s =~ s/\n./\n/gs;

			# Find out how long the conditional actually is.
			my @newlines = ($c =~ /\n/gs);
			my $cond_lines = 1 + $#newlines;

			# We want to check the first line inside the block
			# starting at the end of the conditional, so remove:
			#  1) any blank line termination
			#  2) any opening brace { on end of the line
			#  3) any do (...) {
			my $continuation = 0;
			my $check = 0;
			$s =~ s/^.*\bdo\b//;
			$s =~ s/^\s*{//;
			if ($s =~ s/^\s*\\//) {
				$continuation = 1;
			}
			if ($s =~ s/^\s*?\n//) {
				$check = 1;
				$cond_lines++;
			}

			# Also ignore a loop construct at the end of a
			# preprocessor statement.
			if (($prevline =~ /^.\s*#\s*define\s/ ||
			    $prevline =~ /\\\s*$/) && $continuation == 0) {
				$check = 0;
			}

			my $cond_ptr = -1;
			$continuation = 0;
			while ($cond_ptr != $cond_lines) {
				$cond_ptr = $cond_lines;

				# If we see an #else/#elif then the code
				# is not linear.
				if ($s =~ /^\s*\#\s*(?:else|elif)/) {
					$check = 0;
				}

				# Ignore:
				#  1) blank lines, they should be at 0,
				#  2) preprocessor lines, and
				#  3) labels.
				if ($continuation ||
				    $s =~ /^\s*?\n/ ||
				    $s =~ /^\s*#\s*?/ ||
				    $s =~ /^\s*$Ident\s*:/) {
					$continuation = ($s =~ /^.*?\\\n/) ? 1 : 0;
					if ($s =~ s/^.*?\n//) {
						$cond_lines++;
					}
				}
			}

			my (undef, $sindent) = line_stats("+" . $s);
			my $stat_real = raw_line($linenr, $cond_lines);

			# Check if either of these lines are modified, else
			# this is not this patch's fault.
			if (!defined($stat_real) ||
			    $stat !~ /^\+/ && $stat_real !~ /^\+/) {
				$check = 0;
			}
			if (defined($stat_real) && $cond_lines > 1) {
				$stat_real = "[...]\n$stat_real";
			}

			#print "line<$line> prevline<$prevline> indent<$indent> sindent<$sindent> check<$check> continuation<$continuation> s<$s> cond_lines<$cond_lines> stat_real<$stat_real> stat<$stat>\n";

			if ($check && (($sindent % 8) != 0 ||
			    ($sindent <= $indent && $s ne ''))) {
				WARN("SUSPECT_CODE_INDENT",
				     "suspect code indent for conditional statements ($indent, $sindent)\n" . $herecurr . "$stat_real\n");
			}
		}

		# Track the 'values' across context and added lines.
		my $opline = $line; $opline =~ s/^./ /;
		my ($curr_values, $curr_vars) =
				annotate_values($opline . "\n", $prev_values);
		$curr_values = $prev_values . $curr_values;
		if ($dbg_values) {
			my $outline = $opline; $outline =~ s/\t/ /g;
			print "$linenr > .$outline\n";
			print "$linenr > $curr_values\n";
			print "$linenr >  $curr_vars\n";
		}
		$prev_values = substr($curr_values, -1);

#ignore lines not being added
		next if ($line =~ /^[^\+]/);

# TEST: allow direct testing of the type matcher.
		if ($dbg_type) {
			if ($line =~ /^.\s*$Declare\s*$/) {
				ERROR("TEST_TYPE",
				      "TEST: is type\n" . $herecurr);
			} elsif ($dbg_type > 1 && $line =~ /^.+($Declare)/) {
				ERROR("TEST_NOT_TYPE",
				      "TEST: is not type ($1 is)\n". $herecurr);
			}
			next;
		}
# TEST: allow direct testing of the attribute matcher.
		if ($dbg_attr) {
			if ($line =~ /^.\s*$Modifier\s*$/) {
				ERROR("TEST_ATTR",
				      "TEST: is attr\n" . $herecurr);
			} elsif ($dbg_attr > 1 && $line =~ /^.+($Modifier)/) {
				ERROR("TEST_NOT_ATTR",
				      "TEST: is not attr ($1 is)\n". $herecurr);
			}
			next;
		}

# check for initialisation to aggregates open brace on the next line
		if ($line =~ /^.\s*{/ &&
		    $prevline =~ /(?:^|[^=])=\s*$/) {
			ERROR("OPEN_BRACE",
			      "that open brace { should be on the previous line\n" . $hereprev);
		}

#
# Checks which are anchored on the added line.
#

# check for malformed paths in #include statements (uses RAW line)
		if ($rawline =~ m{^.\s*\#\s*include\s+[<"](.*)[">]}) {
			my $path = $1;
			if ($path =~ m{//}) {
				ERROR("MALFORMED_INCLUDE",
				      "malformed #include filename\n" . $herecurr);
			}
			if ($path =~ "^uapi/" && $realfile =~ m@\binclude/uapi/@) {
				ERROR("UAPI_INCLUDE",
				      "No #include in ...include/uapi/... should use a uapi/ path prefix\n" . $herecurr);
			}
		}

# no C99 // comments
		if ($line =~ m{//}) {
			if (ERROR("C99_COMMENTS",
				  "do not use C99 // comments\n" . $herecurr) &&
			    $fix) {
				my $line = $fixed[$linenr - 1];
				if ($line =~ /\/\/(.*)$/) {
					my $comment = trim($1);
					$fixed[$linenr - 1] =~ s@\/\/(.*)$@/\* $comment \*/@;
				}
			}
		}
		# Remove C99 comments.
		$line =~ s@//.*@@;
		$opline =~ s@//.*@@;

# EXPORT_SYMBOL should immediately follow the thing it is exporting, consider
# the whole statement.
#print "APW <$lines[$realline_next - 1]>\n";
		if (defined $realline_next &&
		    exists $lines[$realline_next - 1] &&
		    !defined $suppress_export{$realline_next} &&
		    ($lines[$realline_next - 1] =~ /EXPORT_SYMBOL.*\((.*)\)/ ||
		     $lines[$realline_next - 1] =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
			# Handle definitions which produce identifiers with
			# a prefix:
			#   XXX(foo);
			#   EXPORT_SYMBOL(something_foo);
			my $name = $1;
			if ($stat =~ /^(?:.\s*}\s*\n)?.([A-Z_]+)\s*\(\s*($Ident)/ &&
			    $name =~ /^${Ident}_$2/) {
#print "FOO C name<$name>\n";
				$suppress_export{$realline_next} = 1;

			} elsif ($stat !~ /(?:
				\n.}\s*$|
				^.DEFINE_$Ident\(\Q$name\E\)|
				^.DECLARE_$Ident\(\Q$name\E\)|
				^.LIST_HEAD\(\Q$name\E\)|
				^.(?:$Storage\s+)?$Type\s*\(\s*\*\s*\Q$name\E\s*\)\s*\(|
				\b\Q$name\E(?:\s+$Attribute)*\s*(?:;|=|\[|\()
			    )/x) {
#print "FOO A<$lines[$realline_next - 1]> stat<$stat> name<$name>\n";
				$suppress_export{$realline_next} = 2;
			} else {
				$suppress_export{$realline_next} = 1;
			}
		}
		if (!defined $suppress_export{$linenr} &&
		    $prevline =~ /^.\s*$/ &&
		    ($line =~ /EXPORT_SYMBOL.*\((.*)\)/ ||
		     $line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
#print "FOO B <$lines[$linenr - 1]>\n";
			$suppress_export{$linenr} = 2;
		}
		if (defined $suppress_export{$linenr} &&
		    $suppress_export{$linenr} == 2) {
			WARN("EXPORT_SYMBOL",
			     "EXPORT_SYMBOL(foo); should immediately follow its function/variable\n" . $herecurr);
		}

# check for global initialisers.
		if ($line =~ /^\+(\s*$Type\s*$Ident\s*(?:\s+$Modifier))*\s*=\s*(0|NULL|false)\s*;/) {
			if (ERROR("GLOBAL_INITIALISERS",
				  "do not initialise globals to 0 or NULL\n" .
				      $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/($Type\s*$Ident\s*(?:\s+$Modifier))*\s*=\s*(0|NULL|false)\s*;/$1;/;
			}
		}
# check for static initialisers.
		if ($line =~ /^\+.*\bstatic\s.*=\s*(0|NULL|false)\s*;/) {
			if (ERROR("INITIALISED_STATIC",
				  "do not initialise statics to 0 or NULL\n" .
				      $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/(\bstatic\s.*?)\s*=\s*(0|NULL|false)\s*;/$1;/;
			}
		}

# check for static const char * arrays.
		if ($line =~ /\bstatic\s+const\s+char\s*\*\s*(\w+)\s*\[\s*\]\s*=\s*/) {
			WARN("STATIC_CONST_CHAR_ARRAY",
			     "static const char * array should probably be static const char * const\n" .
				$herecurr);
               }

# check for static char foo[] = "bar" declarations.
		if ($line =~ /\bstatic\s+char\s+(\w+)\s*\[\s*\]\s*=\s*"/) {
			WARN("STATIC_CONST_CHAR_ARRAY",
			     "static char array declaration should probably be static const char\n" .
				$herecurr);
               }

# check for function declarations without arguments like "int foo()"
		if ($line =~ /(\b$Type\s+$Ident)\s*\(\s*\)/) {
			if (ERROR("FUNCTION_WITHOUT_ARGS",
				  "Bad function definition - $1() should probably be $1(void)\n" . $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/(\b($Type)\s+($Ident))\s*\(\s*\)/$2 $3(void)/;
			}
		}

# check for uses of DEFINE_PCI_DEVICE_TABLE
		if ($line =~ /\bDEFINE_PCI_DEVICE_TABLE\s*\(\s*(\w+)\s*\)\s*=/) {
			if (WARN("DEFINE_PCI_DEVICE_TABLE",
				 "Prefer struct pci_device_id over deprecated DEFINE_PCI_DEVICE_TABLE\n" . $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~ s/\b(?:static\s+|)DEFINE_PCI_DEVICE_TABLE\s*\(\s*(\w+)\s*\)\s*=\s*/static const struct pci_device_id $1\[\] = /;
			}
		}

# check for new typedefs, only function parameters and sparse annotations
# make sense.
		if ($line =~ /\btypedef\s/ &&
		    $line !~ /\btypedef\s+$Type\s*\(\s*\*?$Ident\s*\)\s*\(/ &&
		    $line !~ /\btypedef\s+$Type\s+$Ident\s*\(/ &&
		    $line !~ /\b$typeTypedefs\b/ &&
		    $line !~ /\b__bitwise(?:__|)\b/) {
			WARN("NEW_TYPEDEFS",
			     "do not add new typedefs\n" . $herecurr);
		}

# * goes on variable not on type
		# (char*[ const])
		while ($line =~ m{(\($NonptrType(\s*(?:$Modifier\b\s*|\*\s*)+)\))}g) {
			#print "AA<$1>\n";
			my ($ident, $from, $to) = ($1, $2, $2);

			# Should start with a space.
			$to =~ s/^(\S)/ $1/;
			# Should not end with a space.
			$to =~ s/\s+$//;
			# '*'s should not have spaces between.
			while ($to =~ s/\*\s+\*/\*\*/) {
			}

##			print "1: from<$from> to<$to> ident<$ident>\n";
			if ($from ne $to) {
				if (ERROR("POINTER_LOCATION",
					  "\"(foo$from)\" should be \"(foo$to)\"\n" .  $herecurr) &&
				    $fix) {
					my $sub_from = $ident;
					my $sub_to = $ident;
					$sub_to =~ s/\Q$from\E/$to/;
					$fixed[$linenr - 1] =~
					    s@\Q$sub_from\E@$sub_to@;
				}
			}
		}
		while ($line =~ m{(\b$NonptrType(\s*(?:$Modifier\b\s*|\*\s*)+)($Ident))}g) {
			#print "BB<$1>\n";
			my ($match, $from, $to, $ident) = ($1, $2, $2, $3);

			# Should start with a space.
			$to =~ s/^(\S)/ $1/;
			# Should not end with a space.
			$to =~ s/\s+$//;
			# '*'s should not have spaces between.
			while ($to =~ s/\*\s+\*/\*\*/) {
			}
			# Modifiers should have spaces.
			$to =~ s/(\b$Modifier$)/$1 /;

##			print "2: from<$from> to<$to> ident<$ident>\n";
			if ($from ne $to && $ident !~ /^$Modifier$/) {
				if (ERROR("POINTER_LOCATION",
					  "\"foo${from}bar\" should be \"foo${to}bar\"\n" .  $herecurr) &&
				    $fix) {

					my $sub_from = $match;
					my $sub_to = $match;
					$sub_to =~ s/\Q$from\E/$to/;
					$fixed[$linenr - 1] =~
					    s@\Q$sub_from\E@$sub_to@;
				}
			}
		}

# # 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;
# 		}

		if ($line =~ /\bLINUX_VERSION_CODE\b/) {
			WARN("LINUX_VERSION_CODE",
			     "LINUX_VERSION_CODE should be avoided, code should be for the version to which it is merged\n" . $herecurr);
		}

# check for uses of printk_ratelimit
		if ($line =~ /\bprintk_ratelimit\s*\(/) {
			WARN("PRINTK_RATELIMITED",
"Prefer printk_ratelimited or pr_<level>_ratelimited to printk_ratelimit\n" . $herecurr);
		}

# printk should use KERN_* levels.  Note that follow on printk's on the
# same line do not need a level, so we use the current block context
# to try and find and validate the current printk.  In summary the current
# printk includes all preceding printk's which have no newline on the end.
# we assume the first bad printk is the one to report.
		if ($line =~ /\bprintk\((?!KERN_)\s*"/) {
			my $ok = 0;
			for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
				#print "CHECK<$lines[$ln - 1]\n";
				# we have a preceding printk if it ends
				# with "\n" ignore it, else it is to blame
				if ($lines[$ln - 1] =~ m{\bprintk\(}) {
					if ($rawlines[$ln - 1] !~ m{\\n"}) {
						$ok = 1;
					}
					last;
				}
			}
			if ($ok == 0) {
				WARN("PRINTK_WITHOUT_KERN_LEVEL",
				     "printk() should include KERN_ facility level\n" . $herecurr);
			}
		}

		if ($line =~ /\bprintk\s*\(\s*KERN_([A-Z]+)/) {
			my $orig = $1;
			my $level = lc($orig);
			$level = "warn" if ($level eq "warning");
			my $level2 = $level;
			$level2 = "dbg" if ($level eq "debug");
			WARN("PREFER_PR_LEVEL",
			     "Prefer netdev_$level2(netdev, ... then dev_$level2(dev, ... then pr_$level(...  to printk(KERN_$orig ...\n" . $herecurr);
		}

		if ($line =~ /\bpr_warning\s*\(/) {
			if (WARN("PREFER_PR_LEVEL",
				 "Prefer pr_warn(... to pr_warning(...\n" . $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~
				    s/\bpr_warning\b/pr_warn/;
			}
		}

		if ($line =~ /\bdev_printk\s*\(\s*KERN_([A-Z]+)/) {
			my $orig = $1;
			my $level = lc($orig);
			$level = "warn" if ($level eq "warning");
			$level = "dbg" if ($level eq "debug");
			WARN("PREFER_DEV_LEVEL",
			     "Prefer dev_$level(... to dev_printk(KERN_$orig, ...\n" . $herecurr);
		}

# function brace can't be on same line, except for #defines of do while,
# or if closed on same line
		if (($line=~/$Type\s*$Ident\(.*\).*\s\{/) and
		    !($line=~/\#\s*define.*do\s\{/) and !($line=~/}/)) {
			ERROR("OPEN_BRACE",
			      "open brace '{' following function declarations go on the next line\n" . $herecurr);
		}

# open braces for enum, union and struct go on the same line.
		if ($line =~ /^.\s*{/ &&
		    $prevline =~ /^.\s*(?:typedef\s+)?(enum|union|struct)(?:\s+$Ident)?\s*$/) {
			ERROR("OPEN_BRACE",
			      "open brace '{' following $1 go on the same line\n" . $hereprev);
		}

# missing space after union, struct or enum definition
		if ($line =~ /^.\s*(?:typedef\s+)?(enum|union|struct)(?:\s+$Ident){1,2}[=\{]/) {
			if (WARN("SPACING",
				 "missing space after $1 definition\n" . $herecurr) &&
			    $fix) {
				$fixed[$linenr - 1] =~
				    s/^(.\s*(?:typedef\s+)?(?:enum|union|struct)(?:\s+$Ident){1,2})([=\{])/$1 $2/;
			}
		}

# Function pointer declarations
# check spacing between type, funcptr, and args
# canonical declaration is "type (*funcptr)(args...)"
#
# the $Declare variable will capture all spaces after the type
# so check it for trailing missing spaces or multiple spaces
		if ($line =~ /^.\s*($Declare)\((\s*)\*(\s*)$Ident(\s*)\)(\s*)\(/) {
			my $declare = $1;
			my $pre_pointer_space = $2;
			my $post_pointer_space = $3;
			my $funcname = $4;
			my $post_funcname_space = $5;
			my $pre_args_space = $6;

			if ($declare !~ /\s$/) {
				WARN("SPACING",
				     "missing space after return type\n" . $herecurr);
			}

# unnecessary space "type  (*funcptr)(args...)"
			elsif ($declare =~ /\s{2,}$/) {
				WARN("SPACING",
				     "Multiple spaces after return type\n" . $herecurr);
			}

# unnecessary space "type ( *funcptr)(args...)"
			if (defined $pre_pointer_space &&
			    $pre_pointer_space =~ /^\s/) {
				WARN("SPACING",
				     "Unnecessary space after function pointer open parenthesis\n" . $herecurr);
			}

# unnecessary space "type (* funcptr)(args...)"
			if (defined $post_pointer_space &&
			    $post_pointer_space =~ /^\s/) {
				WARN("SPACING",
				     "Unnecessary space before function pointer name\n" . $herecurr);
			}

# unnecessary space "type (*funcptr )(args...)"
			if (defined $post_funcname_space &&
			    $post_funcname_space =~ /^\s/) {
				WARN("SPACING",
				     "Unnecessary space after function pointer name\n" . $herecurr);
			}

# unnecessary space "type (*funcptr) (args...)"
			if (defined $pre_args_space &&
			    $pre_args_space =~ /^\s/) {
				WARN("SPACING",
				     "Unnecessary space before function pointer arguments\n" . $herecurr);
			}

			if (show_type("SPACING") && $fix) {
				$fixed[$linenr - 1] =~
				    s/^(.\s*$Declare)\(\s*\*\s*($Ident)\s*\)\s*\(/rtrim($1) . " " . "\(\*$2\)\("/ex;
			}
		}

# check for spacing round square brackets; allowed:
#  1. with a type on the left -- int [] a;
#  2. at the beginning of a line for slice initialisers -- [0...10] = 5,
#  3. inside a curly brace -- = { [0...10] = 5 }
		while ($line =~ /(.*?\s)\[/g) {
			my ($where, $prefix) = ($-[1], $1);
			if ($prefix !~ /$Type\s+$/ &&
			    ($where != 0 || $prefix !~ /^.\s+$/) &&
			    $prefix !~ /[{,]\s+$/) {
				if (ERROR("BRACKET_SPACE",
					  "space prohibited before open square bracket '['\n" . $herecurr) &&
				    $fix) {
				    $fixed[$linenr - 1] =~
					s/^(\+.*?)\s+\[/$1\[/;
				}
			}
		}

# check for spaces between functions and their parentheses.
		while ($line =~ /($Ident)\s+\(/g) {
			my $name = $1;
			my $ctx_before = substr($line, 0, $-[1]);
			my $ctx = "$ctx_before$name";

			# Ignore those directives where spaces _are_ permitted.
			if ($name =~ /^(?:
				if|for|while|switch|return|case|
				volatile|__volatile__|
				__attribute__|format|__extension__|
				asm|__asm__)$/x)
			{
			# cpp #define statements have non-optional spaces, ie
			# if there is a space between the name and the open
			# parenthesis it is simply not a parameter group.
			} elsif ($ctx_before =~ /^.\s*\#\s*define\s*$/) {

			# cpp #elif statement condition may start with a (
			} elsif ($ctx =~ /^.\s*\#\s*elif\s*$/) {

			# If this whole things ends with a type its most
			# likely a typedef for a function.
			} elsif ($ctx =~ /$Type$/) {

			} else {
				if (WARN("SPACING",
					 "space prohibited between function name and open parenthesis '('\n" . $herecurr) &&
					     $fix) {
					$fixed[$linenr - 1] =~
					    s/\b$name\s+\(/$name\(/;
				}
			}
		}

# Check operator spacing.
		if (!($line=~/\#\s*include/)) {
			my $fixed_line = "";
			my $line_fixed = 0;

			my $ops = qr{
				<<=|>>=|<=|>=|==|!=|
				\+=|-=|\*=|\/=|%=|\^=|\|=|&=|
				=>|->|<<|>>|<|>|=|!|~|
				&&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/|%|
				\?:|\?|:
			}x;
			my @elements = split(/($ops|;)/, $opline);

##			print("element count: <" . $#elements . ">\n");
##			foreach my $el (@elements) {
##				print("el: <$el>\n");
##			}

			my @fix_elements = ();
			my $off = 0;

			foreach my $el (@elements) {
				push(@fix_elements, substr($rawline, $off, length($el)));
				$off += length($el);
			}

			$off = 0;

			my $blank = copy_spacing($opline);
			my $last_after = -1;

			for (my $n = 0; $n < $#elements; $n += 2) {

				my $good = $fix_elements[$n] . $fix_elements[$n + 1];

##				print("n: <$n> good: <$good>\n");