scripts/checkpatch.pl

#!/usr/bin/env perl
# (c) 2001, Dave Jones. (the file handling bit)
# (c) 2005, Joel Schopp <jschopp@austin.ibm.com> (the ugly bit)
# (c) 2007,2008, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite)
# (c) 2008-2010 Andy Whitcroft <apw@canonical.com>
# Licensed under the terms of the GNU GPL License version 2

use strict;
use warnings;
use Term::ANSIColor qw(:constants);

my $P = $0;
$P =~ s@.*/@@g;

our $SrcFile    = qr{\.(?:(h|c)(\.inc)?|cpp|s|S|pl|py|sh)$};

my $V = '0.31';

use Getopt::Long qw(:config no_auto_abbrev);

my $quiet = 0;
my $tree = 1;
my $chk_signoff = 1;
my $chk_patch = undef;
my $chk_branch = undef;
my $tst_only;
my $emacs = 0;
my $terse = 0;
my $file = undef;
my $color = "auto";
my $no_warnings = 0;
my $summary = 1;
my $mailback = 0;
my $summary_file = 0;
my $root;
my %debug;
my $help = 0;
my $codespell = 0;
my $codespellfile = "/usr/share/codespell/dictionary.txt";
my $user_codespellfile = "";

sub help {
	my ($exitcode) = @_;

	print << "EOM";
Usage:

    $P [OPTION]... [FILE]...
    $P [OPTION]... [GIT-REV-LIST]

Version: $V

Options:
  -q, --quiet                quiet
  --no-tree                  run without a qemu tree
  --no-signoff               do not check for 'Signed-off-by' line
  --patch                    treat FILE as patchfile
  --branch                   treat args as GIT revision list
  --emacs                    emacs compile window format
  --terse                    one line per report
  -f, --file                 treat FILE as regular source file
  --strict                   fail if only warnings are found
  --root=PATH                PATH to the qemu tree root
  --no-summary               suppress the per-file summary
  --mailback                 only produce a report in case of warnings/errors
  --summary-file             include the filename in summary
  --debug KEY=[0|1]          turn on/off debugging of KEY, where KEY is one of
                             'values', 'possible', 'type', and 'attr' (default
                             is all off)
  --test-only=WORD           report only warnings/errors containing WORD
                             literally
  --codespell                Use the codespell dictionary for spelling/typos
                             (default: $codespellfile)
  --codespellfile            Use this codespell dictionary
  --color[=WHEN]             Use colors 'always', 'never', or only when output
                             is a terminal ('auto'). Default is 'auto'.
  -h, --help, --version      display this help and exit

When FILE is - read standard input.
EOM

	exit($exitcode);
}

# Perl's Getopt::Long allows options to take optional arguments after a space.
# Prevent --color by itself from consuming other arguments
foreach (@ARGV) {
	if ($_ eq "--color" || $_ eq "-color") {
		$_ = "--color=$color";
	}
}

GetOptions(
	'q|quiet+'		=> \$quiet,
	'tree!'			=> \$tree,
	'signoff!'		=> \$chk_signoff,
	'patch!'		=> \$chk_patch,
	'branch!'		=> \$chk_branch,
	'emacs!'		=> \$emacs,
	'terse!'		=> \$terse,
	'f|file!'		=> \$file,
	'strict!'		=> \$no_warnings,
	'root=s'		=> \$root,
	'summary!'		=> \$summary,
	'mailback!'		=> \$mailback,
	'summary-file!'		=> \$summary_file,
	'debug=s'		=> \%debug,
	'test-only=s'		=> \$tst_only,
	'codespell!'		=> \$codespell,
	'codespellfile=s'	=> \$user_codespellfile,
	'color=s'		=> \$color,
	'no-color'		=> sub { $color = 'never'; },
	'h|help'		=> \$help,
	'version'		=> \$help
) or help(1);

if ($user_codespellfile) {
	# Use the user provided codespell file unconditionally
	$codespellfile = $user_codespellfile;
} elsif (!(-f $codespellfile)) {
	# If /usr/share/codespell/dictionary.txt is not present, try to find it
	# under codespell's install directory: <codespell_root>/data/dictionary.txt
	if (($codespell || $help) && which("python3") ne "") {
		my $python_codespell_dict = << "EOF";

import os.path as op
import codespell_lib
codespell_dir = op.dirname(codespell_lib.__file__)
codespell_file = op.join(codespell_dir, 'data', 'dictionary.txt')
print(codespell_file, end='')
EOF

		my $codespell_dict = `python3 -c "$python_codespell_dict" 2> /dev/null`;
		$codespellfile = $codespell_dict if (-f $codespell_dict);
	}
}

help(0) if ($help);

my $exit = 0;

if ($#ARGV < 0) {
	print "$P: no input files\n";
	exit(1);
}

if (!defined $chk_branch && !defined $chk_patch && !defined $file) {
	$chk_branch = $ARGV[0] =~ /.\.\./ ? 1 : 0;
	$file = $ARGV[0] =~ /$SrcFile/ ? 1 : 0;
	$chk_patch = $chk_branch || $file ? 0 : 1;
} elsif (!defined $chk_branch && !defined $chk_patch) {
	if ($file) {
		$chk_branch = $chk_patch = 0;
	} else {
		$chk_branch = $ARGV[0] =~ /.\.\./ ? 1 : 0;
		$chk_patch = $chk_branch ? 0 : 1;
	}
} elsif (!defined $chk_branch && !defined $file) {
	if ($chk_patch) {
		$chk_branch = $file = 0;
	} else {
		$chk_branch = $ARGV[0] =~ /.\.\./ ? 1 : 0;
		$file = $chk_branch ? 0 : 1;
	}
} elsif (!defined $chk_patch && !defined $file) {
	if ($chk_branch) {
		$chk_patch = $file = 0;
	} else {
		$file = $ARGV[0] =~ /$SrcFile/ ? 1 : 0;
		$chk_patch = $file ? 0 : 1;
	}
} elsif (!defined $chk_branch) {
	$chk_branch = $chk_patch || $file ? 0 : 1;
} elsif (!defined $chk_patch) {
	$chk_patch = $chk_branch || $file ? 0 : 1;
} elsif (!defined $file) {
	$file = $chk_patch || $chk_branch ? 0 : 1;
}

if (($chk_patch && $chk_branch) ||
    ($chk_patch && $file) ||
    ($chk_branch && $file)) {
	die "Only one of --file, --branch, --patch is permitted\n";
}
if (!$chk_patch && !$chk_branch && !$file) {
	die "One of --file, --branch, --patch is required\n";
}

if ($color =~ /^always$/i) {
	$color = 1;
} elsif ($color =~ /^never$/i) {
	$color = 0;
} elsif ($color =~ /^auto$/i) {
	$color = (-t STDOUT);
} else {
	die "Invalid color mode: $color\n";
}

my $dbg_values = 0;
my $dbg_possible = 0;
my $dbg_type = 0;
my $dbg_attr = 0;
my $dbg_adv_dcs = 0;
my $dbg_adv_checking = 0;
my $dbg_adv_apw = 0;
for my $key (keys %debug) {
	## no critic
	eval "\${dbg_$key} = '$debug{$key}';";
	die "$@" if ($@);
}

my $rpt_cleaners = 0;

if ($terse) {
	$emacs = 1;
	$quiet++;
}

if ($tree) {
	if (defined $root) {
		if (!top_of_kernel_tree($root)) {
			die "$P: $root: --root does not point at a valid tree\n";
		}
	} else {
		if (top_of_kernel_tree('.')) {
			$root = '.';
		} elsif ($0 =~ m@(.*)/scripts/[^/]*$@ &&
						top_of_kernel_tree($1)) {
			$root = $1;
		}
	}

	if (!defined $root) {
		print "Must be run from the top-level dir. of a qemu tree\n";
		exit(2);
	}
}

my $emitted_corrupt = 0;

our $Ident	= qr{
			[A-Za-z_][A-Za-z\d_]*
			(?:\s*\#\#\s*[A-Za-z_][A-Za-z\d_]*)*
		}x;
our $Storage	= qr{extern|static|asmlinkage};
our $Sparse	= qr{
			__force
		}x;

# Notes to $Attribute:
our $Attribute	= qr{
			const|
			volatile|
			G_NORETURN|
			G_GNUC_WARN_UNUSED_RESULT|
			G_GNUC_NULL_TERMINATED|
			QEMU_PACKED|
			G_GNUC_PRINTF
		  }x;
our $Modifier;
our $Inline	= qr{inline};
our $Member	= qr{->$Ident|\.$Ident|\[[^]]*\]};
our $Lval	= qr{$Ident(?:$Member)*};

our $Constant	= qr{(?:[0-9]+|0x[0-9a-fA-F]+)[UL]*};
our $Assignment	= qr{(?:\*\=|/=|%=|\+=|-=|<<=|>>=|&=|\^=|\|=|=)};
our $Compare    = qr{<=|>=|==|!=|<|>};
our $Operators	= qr{
			<=|>=|==|!=|
			=>|->|<<|>>|<|>|!|~|
			&&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/|%
		  }x;

our $NonptrType;
our $Type;
our $Declare;

our $NON_ASCII_UTF8	= qr{
	[\xC2-\xDF][\x80-\xBF]               # non-overlong 2-byte
	|  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
	| [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
	|  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
	|  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
	| [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
	|  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
}x;

our $UTF8	= qr{
	[\x09\x0A\x0D\x20-\x7E]              # ASCII
	| $NON_ASCII_UTF8
}x;

# some readers default to ISO-8859-1 when showing email source. detect
# when UTF-8 is incorrectly interpreted as ISO-8859-1 and reencoded back.
# False positives are possible but very unlikely.
our $UTF8_MOJIBAKE = qr{
	\xC3[\x82-\x9F] \xC2[\x80-\xBF]                    # c2-df 80-bf
	| \xC3\xA0 \xC2[\xA0-\xBF] \xC2[\x80-\xBF]         # e0 a0-bf 80-bf
	| \xC3[\xA1-\xAC\xAE\xAF] (?: \xC2[\x80-\xBF]){2}  # e1-ec/ee/ef 80-bf 80-bf
	| \xC3\xAD \xC2[\x80-\x9F] \xC2[\x80-\xBF]         # ed 80-9f 80-bf
	| \xC3\xB0 \xC2[\x90-\xBF] (?: \xC2[\x80-\xBF]){2} # f0 90-bf 80-bf 80-bf
	| \xC3[\xB1-\xB3] (?: \xC2[\x80-\xBF]){3}          # f1-f3 80-bf 80-bf 80-bf
	| \xC3\xB4 \xC2[\x80-\x8F] (?: \xC2[\x80-\xBF]){2} # f4 80-b8 80-bf 80-bf
}x;

# There are still some false positives, but this catches most
# common cases.
our $typeTypedefs = qr{(?x:
        (?![KMGTPE]iB)                      # IEC binary prefix (do not match)
        [A-Z][A-Z\d_]*[a-z][A-Za-z\d_]*     # camelcase
        | [A-Z][A-Z\d_]*AIOCB               # all uppercase
        | [A-Z][A-Z\d_]*CPU                 # all uppercase
        | QEMUBH                            # all uppercase
)};

our @typeList = (
	qr{void},
	qr{(?:unsigned\s+)?char},
	qr{(?:unsigned\s+)?short},
	qr{(?:unsigned\s+)?int},
	qr{(?:unsigned\s+)?long},
	qr{(?:unsigned\s+)?long\s+int},
	qr{(?:unsigned\s+)?long\s+long},
	qr{(?:unsigned\s+)?long\s+long\s+int},
	qr{unsigned},
	qr{float},
	qr{double},
	qr{bool},
	qr{struct\s+$Ident},
	qr{union\s+$Ident},
	qr{enum\s+$Ident},
	qr{${Ident}_t},
	qr{${Ident}_handler},
	qr{${Ident}_handler_fn},
	qr{target_(?:u)?long},
	qr{hwaddr},
        # external libraries
	qr{xen\w+_handle},
	# Glib definitions
	qr{gchar},
	qr{gshort},
	qr{glong},
	qr{gint},
	qr{gboolean},
	qr{guchar},
	qr{gushort},
	qr{gulong},
	qr{guint},
	qr{gfloat},
	qr{gdouble},
	qr{gpointer},
	qr{gconstpointer},
	qr{gint8},
	qr{guint8},
	qr{gint16},
	qr{guint16},
	qr{gint32},
	qr{guint32},
	qr{gint64},
	qr{guint64},
	qr{gsize},
	qr{gssize},
	qr{goffset},
	qr{gintptr},
	qr{guintptr},
);

# Match text found in common license boilerplate comments:
# for new files the SPDX-License-Identifier line is sufficient.
our @LICENSE_BOILERPLATE = (
	"licensed under the terms of the GNU GPL",
	"under the terms of the GNU General Public License",
	"under the terms of the GNU Lesser General Public",
	"Permission is hereby granted, free of charge",
	"GNU GPL, version 2 or later",
	"See the COPYING file"
);
our $LICENSE_BOILERPLATE_RE = join("|", @LICENSE_BOILERPLATE);

# Load common spelling mistakes and build regular expression list.
my $misspellings;
my %spelling_fix;

if ($codespell) {
	if (open(my $spelling, '<', $codespellfile)) {
		while (<$spelling>) {
			my $line = $_;

			$line =~ s/\s*\n?$//g;
			$line =~ s/^\s*//g;

			next if ($line =~ m/^\s*#/);
			next if ($line =~ m/^\s*$/);
			next if ($line =~ m/, disabled/i);

			$line =~ s/,.*$//;

			my ($suspect, $fix) = split(/->/, $line);

			$spelling_fix{$suspect} = $fix;
		}
		close($spelling);
	} else {
		warn "No codespell typos will be found - file '$codespellfile': $!\n";
	}
}

$misspellings = join("|", sort keys %spelling_fix) if keys %spelling_fix;

# This can be modified by sub possible.  Since it can be empty, be careful
# about regexes that always match, because they can cause infinite loops.
our @modifierList = (
);

sub build_types {
	my $all = "(?x:  \n" . join("|\n  ", @typeList) . "\n)";
	if (@modifierList > 0) {
		my $mods = "(?x:  \n" . join("|\n  ", @modifierList) . "\n)";
		$Modifier = qr{(?:$Attribute|$Sparse|$mods)};
	} else {
		$Modifier = qr{(?:$Attribute|$Sparse)};
	}
	$NonptrType	= qr{
			(?:$Modifier\s+|const\s+)*
			(?:
				(?:typeof|__typeof__)\s*\(\s*\**\s*$Ident\s*\)|
				(?:$typeTypedefs\b)|
				(?:${all}\b)
			)
			(?:\s+$Modifier|\s+const)*
		  }x;
	$Type	= qr{
			$NonptrType
			(?:[\s\*]+\s*const|[\s\*]+|(?:\s*\[\s*\])+)?
			(?:\s+$Inline|\s+$Modifier)*
		  }x;
	$Declare	= qr{(?:$Storage\s+)?$Type};
}
build_types();

$chk_signoff = 0 if ($file);

my @rawlines = ();
my @lines = ();
my $vname;
if ($chk_branch) {
	my @patches;
	my %git_commits = ();
	my $HASH;
	open($HASH, "-|", "git", "log", "--reverse", "--no-merges", "--no-mailmap", "--format=%H %s", $ARGV[0]) ||
		die "$P: git log --reverse --no-merges --no-mailmap --format='%H %s' $ARGV[0] failed - $!\n";

	for my $line (<$HASH>) {
		$line =~ /^([0-9a-fA-F]{40,40}) (.*)$/;
		next if (!defined($1) || !defined($2));
		my $sha1 = $1;
		my $subject = $2;
		push(@patches, $sha1);
		$git_commits{$sha1} = $subject;
	}

	close $HASH;

	die "$P: no revisions returned for revlist '$ARGV[0]'\n"
	    unless @patches;

	my $i = 1;
	my $num_patches = @patches;
	for my $hash (@patches) {
		my $FILE;
		open($FILE, '-|', "git",
                     "-c", "diff.renamelimit=0",
                     "-c", "diff.renames=True",
                     "-c", "diff.algorithm=histogram",
                     "show", "--no-mailmap",
                     "--patch-with-stat", $hash) ||
			die "$P: git show $hash - $!\n";
		while (<$FILE>) {
			chomp;
			push(@rawlines, $_);
		}
		close($FILE);
		$vname = substr($hash, 0, 12) . ' (' . $git_commits{$hash} . ')';
		if ($num_patches > 1 && $quiet == 0) {
			my $prefix = "$i/$num_patches";
			$prefix = BLUE . BOLD . $prefix . RESET if $color;
			print "$prefix Checking commit $vname\n";
			$vname = "Patch $i/$num_patches";
		} else {
			$vname = "Commit " . $vname;
		}
		if (!process($hash)) {
			$exit = 1;
			print "\n" if ($num_patches > 1 && $quiet == 0);
		}
		@rawlines = ();
		@lines = ();
		$i++;
	}
} else {
	for my $filename (@ARGV) {
		my $FILE;
		if ($file) {
			open($FILE, '-|', "diff -u /dev/null $filename") ||
				die "$P: $filename: diff failed - $!\n";
		} elsif ($filename eq '-') {
			open($FILE, '<&STDIN');
		} else {
			open($FILE, '<', "$filename") ||
				die "$P: $filename: open failed - $!\n";
		}
		if ($filename eq '-') {
			$vname = 'Your patch';
		} else {
			$vname = $filename;
		}
		print "Checking $filename...\n" if @ARGV > 1 && $quiet == 0;
		while (<$FILE>) {
			chomp;
			push(@rawlines, $_);
		}
		close($FILE);
		if (!process($filename)) {
			$exit = 1;
		}
		@rawlines = ();
		@lines = ();
	}
}

exit($exit);

sub top_of_kernel_tree {
	my ($root) = @_;

	my @tree_check = (
		"COPYING", "MAINTAINERS", "Makefile",
		"README.rst", "docs", "VERSION",
		"linux-user", "system"
	);

	foreach my $check (@tree_check) {
		if (! -e $root . '/' . $check) {
			return 0;
		}
	}
	return 1;
}

sub which {
	my ($bin) = @_;

	foreach my $path (split(/:/, $ENV{PATH})) {
		if (-e "$path/$bin") {
			return "$path/$bin";
		}
	}

	return "";
}

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 copy_spacing {
	(my $res = shift) =~ tr/\t/ /c;
	return $res;
}

sub line_stats {
	my ($line) = @_;

	# Drop the diff line leader and expand tabs
	$line =~ s/^.//;
	$line = expand_tabs($line);

	# Pick the indent from the front of the line.
	my ($white) = ($line =~ /^(\s*)/);

	return (length($line), length($white));
}

my $sanitise_quote = '';

sub sanitise_line_reset {
	my ($in_comment) = @_;

	if ($in_comment) {
		$sanitise_quote = '*/';
	} else {
		$sanitise_quote = '';
	}
}
sub sanitise_line {
	my ($line) = @_;

	my $res = '';
	my $l = '';

	my $qlen = 0;
	my $off = 0;
	my $c;

	# Always copy over the diff marker.
	$res = substr($line, 0, 1);

	for ($off = 1; $off < length($line); $off++) {
		$c = substr($line, $off, 1);

		# Comments we are wacking completely including the begin
		# and end, all to $;.
		if ($sanitise_quote eq '' && substr($line, $off, 2) eq '/*') {
			$sanitise_quote = '*/';

			substr($res, $off, 2, "$;$;");
			$off++;
			next;
		}
		if ($sanitise_quote eq '*/' && substr($line, $off, 2) eq '*/') {
			$sanitise_quote = '';
			substr($res, $off, 2, "$;$;");
			$off++;
			next;
		}
		if ($sanitise_quote eq '' && substr($line, $off, 2) eq '//') {
			$sanitise_quote = '//';

			substr($res, $off, 2, $sanitise_quote);
			$off++;
			next;
		}

		# A \ in a string means ignore the next character.
		if (($sanitise_quote eq "'" || $sanitise_quote eq '"') &&
		    $c eq "\\") {
			substr($res, $off, 2, 'XX');
			$off++;
			next;
		}
		# Regular quotes.
		if ($c eq "'" || $c eq '"') {
			if ($sanitise_quote eq '') {
				$sanitise_quote = $c;

				substr($res, $off, 1, $c);
				next;
			} elsif ($sanitise_quote eq $c) {
				$sanitise_quote = '';
			}
		}

		#print "c<$c> SQ<$sanitise_quote>\n";
		if ($off != 0 && $sanitise_quote eq '*/' && $c ne "\t") {
			substr($res, $off, 1, $;);
		} elsif ($off != 0 && $sanitise_quote eq '//' && $c ne "\t") {
			substr($res, $off, 1, $;);
		} elsif ($off != 0 && $sanitise_quote && $c ne "\t") {
			substr($res, $off, 1, 'X');
		} else {
			substr($res, $off, 1, $c);
		}
	}

	if ($sanitise_quote eq '//') {
		$sanitise_quote = '';
	}

	# The pathname on a #include may be surrounded by '<' and '>'.
	if ($res =~ /^.\s*\#\s*include\s+\<(.*)\>/) {
		my $clean = 'X' x length($1);
		$res =~ s@\<.*\>@<$clean>@;

	# The whole of a #error is a string.
	} elsif ($res =~ /^.\s*\#\s*(?:error|warning)\s+(.*)\b/) {
		my $clean = 'X' x length($1);
		$res =~ s@(\#\s*(?:error|warning)\s+).*@$1$clean@;
	}

	return $res;
}

sub ctx_statement_block {
	my ($linenr, $remain, $off) = @_;
	my $line = $linenr - 1;
	my $blk = '';
	my $soff = $off;
	my $coff = $off - 1;
	my $coff_set = 0;

	my $loff = 0;

	my $type = '';
	my $level = 0;
	my @stack = ();
	my $p;
	my $c;
	my $len = 0;

	my $remainder;
	while (1) {
		@stack = (['', 0]) if ($#stack == -1);

		#warn "CSB: blk<$blk> remain<$remain>\n";
		# If we are about to drop off the end, pull in more
		# context.
		if ($off >= $len) {
			for (; $remain > 0; $line++) {
				last if (!defined $lines[$line]);
				next if ($lines[$line] =~ /^-/);
				$remain--;
				$loff = $len;
				$blk .= $lines[$line] . "\n";
				$len = length($blk);
				$line++;
				last;
			}
			# Bail if there is no further context.
			#warn "CSB: blk<$blk> off<$off> len<$len>\n";
			if ($off >= $len) {
				last;
			}
		}
		$p = $c;
		$c = substr($blk, $off, 1);
		$remainder = substr($blk, $off);

		#warn "CSB: c<$c> type<$type> level<$level> remainder<$remainder> coff_set<$coff_set>\n";

		# Handle nested #if/#else.
		if ($remainder =~ /^#\s*(?:ifndef|ifdef|if)\s/) {
			push(@stack, [ $type, $level ]);
		} elsif ($remainder =~ /^#\s*(?:else|elif)\b/) {
			($type, $level) = @{$stack[$#stack - 1]};
		} elsif ($remainder =~ /^#\s*endif\b/) {
			($type, $level) = @{pop(@stack)};
		}

		# Statement ends at the ';' or a close '}' at the
		# outermost level.
		if ($level == 0 && $c eq ';') {
			last;
		}

		# An else is really a conditional as long as its not else if
		if ($level == 0 && $coff_set == 0 &&
				(!defined($p) || $p =~ /(?:\s|\}|\+)/) &&
				$remainder =~ /^(else)(?:\s|{)/ &&
				$remainder !~ /^else\s+if\b/) {
			$coff = $off + length($1) - 1;
			$coff_set = 1;
			#warn "CSB: mark coff<$coff> soff<$soff> 1<$1>\n";
			#warn "[" . substr($blk, $soff, $coff - $soff + 1) . "]\n";
		}

		if (($type eq '' || $type eq '(') && $c eq '(') {
			$level++;
			$type = '(';
		}
		if ($type eq '(' && $c eq ')') {
			$level--;
			$type = ($level != 0)? '(' : '';

			if ($level == 0 && $coff < $soff) {
				$coff = $off;
				$coff_set = 1;
				#warn "CSB: mark coff<$coff>\n";
			}
		}
		if (($type eq '' || $type eq '{') && $c eq '{') {
			$level++;
			$type = '{';
		}
		if ($type eq '{' && $c eq '}') {
			$level--;
			$type = ($level != 0)? '{' : '';

			if ($level == 0) {
				if (substr($blk, $off + 1, 1) eq ';') {
					$off++;
				}
				last;
			}
		}
		$off++;
	}
	# We are truly at the end, so shuffle to the next line.
	if ($off == $len) {
		$loff = $len + 1;
		$line++;
		$remain--;
	}

	my $statement = substr($blk, $soff, $off - $soff + 1);
	my $condition = substr($blk, $soff, $coff - $soff + 1);

	#warn "STATEMENT<$statement>\n";
	#warn "CONDITION<$condition>\n";

	#print "coff<$coff> soff<$off> loff<$loff>\n";

	return ($statement, $condition,
			$line, $remain + 1, $off - $loff + 1, $level);
}

sub statement_lines {
	my ($stmt) = @_;

	# Strip the diff line prefixes and rip blank lines at start and end.
	$stmt =~ s/(^|\n)./$1/g;
	$stmt =~ s/^\s*//;
	$stmt =~ s/\s*$//;

	my @stmt_lines = ($stmt =~ /\n/g);

	return $#stmt_lines + 2;
}

sub statement_rawlines {
	my ($stmt) = @_;

	my @stmt_lines = ($stmt =~ /\n/g);

	return $#stmt_lines + 2;
}

sub statement_block_size {
	my ($stmt) = @_;

	$stmt =~ s/(^|\n)./$1/g;
	$stmt =~ s/^\s*\{//;
	$stmt =~ s/}\s*$//;
	$stmt =~ s/^\s*//;
	$stmt =~ s/\s*$//;

	my @stmt_lines = ($stmt =~ /\n/g);
	my @stmt_statements = ($stmt =~ /;/g);

	my $stmt_lines = $#stmt_lines + 2;
	my $stmt_statements = $#stmt_statements + 1;

	if ($stmt_lines > $stmt_statements) {
		return $stmt_lines;
	} else {
		return $stmt_statements;
	}
}

sub ctx_statement_full {
	my ($linenr, $remain, $off) = @_;
	my ($statement, $condition, $level);

	my (@chunks);

	# Grab the first conditional/block pair.
	($statement, $condition, $linenr, $remain, $off, $level) =
				ctx_statement_block($linenr, $remain, $off);
	#print "F: c<$condition> s<$statement> remain<$remain>\n";
	push(@chunks, [ $condition, $statement ]);
	if (!($remain > 0 && $condition =~ /^\s*(?:\n[+-])?\s*(?:if|else|do)\b/s)) {
		return ($level, $linenr, @chunks);
	}

	# Pull in the following conditional/block pairs and see if they
	# could continue the statement.
	for (;;) {
		($statement, $condition, $linenr, $remain, $off, $level) =
				ctx_statement_block($linenr, $remain, $off);
		#print "C: c<$condition> s<$statement> remain<$remain>\n";
		last if (!($remain > 0 && $condition =~ /^(?:\s*\n[+-])*\s*(?:else|do)\b/s));
		#print "C: push\n";
		push(@chunks, [ $condition, $statement ]);
	}

	return ($level, $linenr, @chunks);
}

sub ctx_block_get {
	my ($linenr, $remain, $outer, $open, $close, $off) = @_;
	my $line;
	my $start = $linenr - 1;
	my $blk = '';
	my @o;
	my @c;
	my @res = ();

	my $level = 0;
	my @stack = ($level);
	for ($line = $start; $remain > 0; $line++) {
		next if ($rawlines[$line] =~ /^-/);
		$remain--;

		$blk .= $rawlines[$line];

		# Handle nested #if/#else.
		if ($lines[$line] =~ /^.\s*#\s*(?:ifndef|ifdef|if)\s/) {
			push(@stack, $level);
		} elsif ($lines[$line] =~ /^.\s*#\s*(?:else|elif)\b/) {
			$level = $stack[$#stack - 1];
		} elsif ($lines[$line] =~ /^.\s*#\s*endif\b/) {
			$level = pop(@stack);
		}

		foreach my $c (split(//, $lines[$line])) {
			##print "C<$c>L<$level><$open$close>O<$off>\n";
			if ($off > 0) {
				$off--;
				next;
			}

			if ($c eq $close && $level > 0) {
				$level--;
				last if ($level == 0);
			} elsif ($c eq $open) {
				$level++;
			}
		}

		if (!$outer || $level <= 1) {
			push(@res, $rawlines[$line]);
		}

		last if ($level == 0);
	}

	return ($level, @res);
}
sub ctx_block_outer {
	my ($linenr, $remain) = @_;

	my ($level, @r) = ctx_block_get($linenr, $remain, 1, '{', '}', 0);
	return @r;
}
sub ctx_block {
	my ($linenr, $remain) = @_;

	my ($level, @r) = ctx_block_get($linenr, $remain, 0, '{', '}', 0);
	return @r;
}
sub ctx_statement {
	my ($linenr, $remain, $off) = @_;

	my ($level, @r) = ctx_block_get($linenr, $remain, 0, '(', ')', $off);
	return @r;
}
sub ctx_block_level {
	my ($linenr, $remain) = @_;

	return ctx_block_get($linenr, $remain, 0, '{', '}', 0);
}
sub ctx_statement_level {
	my ($linenr, $remain, $off) = @_;

	return ctx_block_get($linenr, $remain, 0, '(', ')', $off);
}

sub ctx_locate_comment {
	my ($first_line, $end_line) = @_;

	# Catch a comment on the end of the line itself.
	my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*(?:\\\s*)?$@);
	return $current_comment if (defined $current_comment);

	# Look through the context and try and figure out if there is a
	# comment.
	my $in_comment = 0;
	$current_comment = '';
	for (my $linenr = $first_line; $linenr < $end_line; $linenr++) {
		my $line = $rawlines[$linenr - 1];
		#warn "           $line\n";
		if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
			$in_comment = 1;
		}
		if ($line =~ m@/\*@) {
			$in_comment = 1;
		}
		if (!$in_comment && $current_comment ne '') {
			$current_comment = '';
		}
		$current_comment .= $line . "\n" if ($in_comment);
		if ($line =~ m@\*/@) {
			$in_comment = 0;
		}
	}

	chomp($current_comment);
	return($current_comment);
}
sub ctx_has_comment {
	my ($first_line, $end_line) = @_;
	my $cmt = ctx_locate_comment($first_line, $end_line);

	##print "LINE: $rawlines[$end_line - 1 ]\n";
	##print "CMMT: $cmt\n";

	return ($cmt ne '');
}

sub raw_line {
	my ($linenr, $cnt) = @_;

	my $offset = $linenr - 1;
	$cnt++;

	my $line;
	while ($cnt) {
		$line = $rawlines[$offset++];
		next if (defined($line) && $line =~ /^-/);
		$cnt--;
	}

	return $line;
}

sub cat_vet {
	my ($vet) = @_;
	my ($res, $coded);

	$res = '';
	while ($vet =~ /([^[:cntrl:]]*)([[:cntrl:]]|$)/g) {
		$res .= $1;
		if ($2 ne '') {
			$coded = sprintf("^%c", unpack('C', $2) + 64);
			$res .= $coded;
		}
	}
	$res =~ s/$/\$/;

	return $res;
}

my $av_preprocessor = 0;
my $av_pending;
my @av_paren_type;
my $av_pend_colon;

sub annotate_reset {
	$av_preprocessor = 0;
	$av_pending = '_';
	@av_paren_type = ('E');
	$av_pend_colon = 'O';
}

sub annotate_values {
	my ($stream, $type) = @_;

	my $res;
	my $var = '_' x length($stream);
	my $cur = $stream;

	print "$stream\n" if ($dbg_values > 1);

	while (length($cur)) {
		@av_paren_type = ('E') if ($#av_paren_type < 0);
		print " <" . join('', @av_paren_type) .
				"> <$type> <$av_pending>" if ($dbg_values > 1);
		if ($cur =~ /^(\s+)/o) {
			print "WS($1)\n" if ($dbg_values > 1);
			if ($1 =~ /\n/ && $av_preprocessor) {
				$type = pop(@av_paren_type);
				$av_preprocessor = 0;
			}

		} elsif ($cur =~ /^(\(\s*$Type\s*)\)/ && $av_pending eq '_') {
			print "CAST($1)\n" if ($dbg_values > 1);
			push(@av_paren_type, $type);
			$type = 'C';

		} elsif ($cur =~ /^($Type)\s*(?:$Ident|,|\)|\(|\s*$)/) {
			print "DECLARE($1)\n" if ($dbg_values > 1);
			$type = 'T';

		} elsif ($cur =~ /^($Modifier)\s*/) {
			print "MODIFIER($1)\n" if ($dbg_values > 1);
			$type = 'T';

		} elsif ($cur =~ /^(\#\s*define\s*$Ident)(\(?)/o) {
			print "DEFINE($1,$2)\n" if ($dbg_values > 1);
			$av_preprocessor = 1;
			push(@av_paren_type, $type);
			if ($2 ne '') {
				$av_pending = 'N';
			}
			$type = 'E';

		} elsif ($cur =~ /^(\#\s*(?:undef\s*$Ident|include\b))/o) {
			print "UNDEF($1)\n" if ($dbg_values > 1);
			$av_preprocessor = 1;
			push(@av_paren_type, $type);

		} elsif ($cur =~ /^(\#\s*(?:ifdef|ifndef|if))/o) {
			print "PRE_START($1)\n" if ($dbg_values > 1);
			$av_preprocessor = 1;

			push(@av_paren_type, $type);
			push(@av_paren_type, $type);
			$type = 'E';

		} elsif ($cur =~ /^(\#\s*(?:else|elif))/o) {
			print "PRE_RESTART($1)\n" if ($dbg_values > 1);
			$av_preprocessor = 1;

			push(@av_paren_type, $av_paren_type[$#av_paren_type]);

			$type = 'E';

		} elsif ($cur =~ /^(\#\s*(?:endif))/o) {
			print "PRE_END($1)\n" if ($dbg_values > 1);

			$av_preprocessor = 1;

			# Assume all arms of the conditional end as this
			# one does, and continue as if the #endif was not here.
			pop(@av_paren_type);
			push(@av_paren_type, $type);
			$type = 'E';

		} elsif ($cur =~ /^(\\\n)/o) {
			print "PRECONT($1)\n" if ($dbg_values > 1);

		} elsif ($cur =~ /^(__attribute__)\s*\(?/o) {
			print "ATTR($1)\n" if ($dbg_values > 1);
			$av_pending = $type;
			$type = 'N';

		} elsif ($cur =~ /^(sizeof)\s*(\()?/o) {
			print "SIZEOF($1)\n" if ($dbg_values > 1);
			if (defined $2) {
				$av_pending = 'V';
			}
			$type = 'N';

		} elsif ($cur =~ /^(if|while|for)\b/o) {
			print "COND($1)\n" if ($dbg_values > 1);
			$av_pending = 'E';
			$type = 'N';

		} elsif ($cur =~/^(case)/o) {
			print "CASE($1)\n" if ($dbg_values > 1);
			$av_pend_colon = 'C';
			$type = 'N';

		} elsif ($cur =~/^(return|else|goto|typeof|__typeof__)\b/o) {
			print "KEYWORD($1)\n" if ($dbg_values > 1);
			$type = 'N';

		} elsif ($cur =~ /^(\()/o) {
			print "PAREN('$1')\n" if ($dbg_values > 1);
			push(@av_paren_type, $av_pending);
			$av_pending = '_';
			$type = 'N';

		} elsif ($cur =~ /^(\))/o) {
			my $new_type = pop(@av_paren_type);
			if ($new_type ne '_') {
				$type = $new_type;
				print "PAREN('$1') -> $type\n"
							if ($dbg_values > 1);
			} else {
				print "PAREN('$1')\n" if ($dbg_values > 1);
			}

		} elsif ($cur =~ /^($Ident)\s*\(/o) {
			print "FUNC($1)\n" if ($dbg_values > 1);
			$type = 'V';
			$av_pending = 'V';

		} elsif ($cur =~ /^($Ident\s*):(?:\s*\d+\s*(,|=|;))?/) {
			if (defined $2 && $type eq 'C' || $type eq 'T') {
				$av_pend_colon = 'B';
			} elsif ($type eq 'E') {
				$av_pend_colon = 'L';
			}
			print "IDENT_COLON($1,$type>$av_pend_colon)\n" if ($dbg_values > 1);
			$type = 'V';

		} elsif ($cur =~ /^($Ident|$Constant)/o) {
			print "IDENT($1)\n" if ($dbg_values > 1);
			$type = 'V';

		} elsif ($cur =~ /^($Assignment)/o) {
			print "ASSIGN($1)\n" if ($dbg_values > 1);
			$type = 'N';

		} elsif ($cur =~/^(;|{|})/) {
			print "END($1)\n" if ($dbg_values > 1);
			$type = 'E';
			$av_pend_colon = 'O';

		} elsif ($cur =~/^(,)/) {
			print "COMMA($1)\n" if ($dbg_values > 1);
			$type = 'C';

		} elsif ($cur =~ /^(\?)/o) {
			print "QUESTION($1)\n" if ($dbg_values > 1);
			$type = 'N';

		} elsif ($cur =~ /^(:)/o) {
			print "COLON($1,$av_pend_colon)\n" if ($dbg_values > 1);

			substr($var, length($res), 1, $av_pend_colon);
			if ($av_pend_colon eq 'C' || $av_pend_colon eq 'L') {
				$type = 'E';
			} else {
				$type = 'N';
			}
			$av_pend_colon = 'O';

		} elsif ($cur =~ /^(\[)/o) {
			print "CLOSE($1)\n" if ($dbg_values > 1);
			$type = 'N';

		} elsif ($cur =~ /^(-(?![->])|\+(?!\+)|\*|\&\&|\&)/o) {
			my $variant;

			print "OPV($1)\n" if ($dbg_values > 1);
			if ($type eq 'V') {
				$variant = 'B';
			} else {
				$variant = 'U';
			}

			substr($var, length($res), 1, $variant);
			$type = 'N';

		} elsif ($cur =~ /^($Operators)/o) {
			print "OP($1)\n" if ($dbg_values > 1);
			if ($1 ne '++' && $1 ne '--') {
				$type = 'N';
			}

		} elsif ($cur =~ /(^.)/o) {
			print "C($1)\n" if ($dbg_values > 1);
		}
		if (defined $1) {
			$cur = substr($cur, length($1));
			$res .= $type x length($1);
		}
	}

	return ($res, $var);
}

sub possible {
	my ($possible, $line) = @_;
	my $notPermitted = qr{(?:
		^(?:
			$Modifier|
			$Storage|
			$Type|
			DEFINE_\S+
		)$|
		^(?:
			goto|
			return|
			case|
			else|
			asm|__asm__|
			do
		)(?:\s|$)|
		^(?:typedef|struct|enum)\b|
		^\#
	    )}x;
	warn "CHECK<$possible> ($line)\n" if ($dbg_possible > 2);
	if ($possible !~ $notPermitted) {
		# Check for modifiers.
		$possible =~ s/\s*$Storage\s*//g;
		$possible =~ s/\s*$Sparse\s*//g;
		if ($possible =~ /^\s*$/) {

		} elsif ($possible =~ /\s/) {
			$possible =~ s/\s*(?:$Type|\#\#)\s*//g;
			for my $modifier (split(' ', $possible)) {
				if ($modifier !~ $notPermitted) {
					warn "MODIFIER: $modifier ($possible) ($line)\n" if ($dbg_possible);
					push(@modifierList, $modifier);
				}
			}

		} else {
			warn "POSSIBLE: $possible ($line)\n" if ($dbg_possible);
			push(@typeList, $possible);
		}
		build_types();
	} else {
		warn "NOTPOSS: $possible ($line)\n" if ($dbg_possible > 1);
	}
}

my $prefix = '';

sub report {
	my ($level, $msg) = @_;
	if (defined $tst_only && $msg !~ /\Q$tst_only\E/) {
		return 0;
	}

	my $output = '';
	$output .= BOLD if $color;
	$output .= $prefix;
	$output .= RED if $color && $level eq 'ERROR';
	$output .= MAGENTA if $color && $level eq 'WARNING';
	$output .= $level . ':';
	$output .= RESET if $color;
	$output .= ' ' . $msg . "\n";

	$output = (split('\n', $output))[0] . "\n" if ($terse);

	push(our @report, $output);

	return 1;
}
sub report_dump {
	our @report;
}
sub ERROR {
	if (report("ERROR", $_[0])) {
		our $clean = 0;
		our $cnt_error++;
	}
}
sub WARN {
	if (report("WARNING", $_[0])) {
		our $clean = 0;
		our $cnt_warn++;
	}
}

sub checkspdx {
    my ($file, $expr) = @_;

    # Imported Linux headers probably have SPDX tags, but if they
    # don't we're not requiring contributors to fix this, as these
    # files are not expected to be modified locally in QEMU.
    # Also don't accidentally detect own checking code.
    if ($file =~ m,include/standard-headers, ||
	$file =~ m,linux-headers, ||
	$file =~ m,checkpatch.pl,) {
	return;
    }

    my $origexpr = $expr;

    # Flatten sub-expressions
    $expr =~ s/\(|\)/ /g;
    $expr =~ s/OR|AND/ /g;

    # Merge WITH exceptions to the license
    $expr =~ s/\s+WITH\s+/-WITH-/g;

    # Cull more leading/trailing whitespace
    $expr =~ s/^\s*//g;
    $expr =~ s/\s*$//g;

    my @bits = split / +/, $expr;

    my $prefer = "GPL-2.0-or-later";
    my @valid = qw(
	GPL-2.0-only
	LGPL-2.1-only
	LGPL-2.1-or-later
	BSD-2-Clause
	BSD-3-Clause
	MIT
	);

    my $nonpreferred = 0;
    my @unknown = ();
    foreach my $bit (@bits) {
	if ($bit eq $prefer) {
	    next;
	}
	if (grep /^$bit$/, @valid) {
	    $nonpreferred = 1;
	} else {
	    push @unknown, $bit;
	}
    }
    if (@unknown) {
	ERROR("Saw unacceptable licenses '" . join(',', @unknown) .
	      "', valid choices for QEMU are:\n" . join("\n", $prefer, @valid));
    }

    if ($nonpreferred) {
	WARN("Saw acceptable license '$origexpr' but note '$prefer' is " .
	     "preferred for new files unless the code is derived from a " .
	     "source file with an existing declared license that must be " .
	     "retained. Please explain the license choice in the commit " .
	     "message.");
    }
}

# All three of the methods below take a 'file info' record
# which is a hash ref containing
#
#  'isgit': 1 if an enhanced git diff or 0 for a plain diff
#  'githeader': 1 if still parsing git patch header, 0 otherwise
#  'linestart': line number of start of file diff
#  'lineend': line number of end of file diff
#  'filenew': the new filename
#  'fileold': the old filename (same as 'new filename' except
#             for renames in git diffs)
#  'action': one of 'modified' (always) or 'new' or 'deleted' or
#            'renamed' (git diffs only)
#  'mode': file mode for new/deleted files (git diffs only)
#  'similarity': file similarity when renamed (git diffs only)
#  'facts': hash ref for storing any metadata related to checks
#

# Called at the end of each patch, with the list of
# real filenames that were seen in the patch
sub process_file_list {
	my @fileinfos = @_;

	# According to tests/qtest/bios-tables-test.c: do not
	# change expected file in the same commit with adding test
	my @acpi_testexpected;
	my @acpi_nontestexpected;

	foreach my $fileinfo (@fileinfos) {
		# Note: shell script that rebuilds the expected files is in
		# the same directory as files themselves.
		# Note: allowed diff list can be changed both when changing
		#  expected files and when changing tests.
		if ($fileinfo->{filenew} =~ m#^tests/data/acpi/# &&
		    $fileinfo->{filenew} !~ m#^\.sh$#) {
			push @acpi_testexpected, $fileinfo->{filenew};
		} elsif ($fileinfo->{filenew} !~
			 m#^tests/qtest/bios-tables-test-allowed-diff.h$#) {
			push @acpi_nontestexpected, $fileinfo->{filenew};
		}
	}
	if (int(@acpi_testexpected) > 0 and int(@acpi_nontestexpected) > 0) {
		ERROR("Do not add expected files together with tests, " .
		      "follow instructions in " .
		      "tests/qtest/bios-tables-test.c. Files\n\n  " .
		      join("\n  ", @acpi_testexpected) .
		      "\n\nand\n\n  " .
		      join("\n  ", @acpi_nontestexpected) .
		      "\n\nfound in the same patch\n");
	}

	my $sawmaintainers = 0;
	my @maybemaintainers;
	foreach my $fileinfo (@fileinfos) {
		if ($fileinfo->{action} ne "modified" &&
		    $fileinfo->{filenew} !~ m#^tests/data/acpi/#) {
			push @maybemaintainers, $fileinfo->{filenew};
		}
		if ($fileinfo->{filenew} eq "MAINTAINERS") {
			$sawmaintainers = 1;
		}
	}

	# If we don't see a MAINTAINERS update, prod the user to check
	if (int(@maybemaintainers) > 0 && !$sawmaintainers) {
		WARN("added, moved or deleted file(s):\n\n  " .
		     join("\n  ", @maybemaintainers) .
		     "\n\nDoes MAINTAINERS need updating?\n");
	}
}

# Called at the start of processing a diff hunk for a file
sub process_start_of_file {
	my $fileinfo = shift;

	# Check for incorrect file permissions
	if ($fileinfo->{action} eq "new" && ($fileinfo->{mode} & 0111)) {
		my $permhere = $fileinfo->{linestart} . "FILE: " .
			$fileinfo->{filenew} . "\n";
		if ($fileinfo->{filenew} =~
		    /(\bMakefile.*|\.(c|cc|cpp|h|mak|s|S))$/) {
			ERROR("do not set execute permissions for source " .
			      "files\n" . $permhere);
		}
	}
}

# Called at the end of processing a diff hunk for a file
sub process_end_of_file {
	my $fileinfo = shift;

	if ($fileinfo->{action} eq "new" &&
	    !exists $fileinfo->{facts}->{sawspdx}) {
		if ($fileinfo->{filenew} =~
		    /(\.(c|h|py|pl|sh|json|inc|rs)|Makefile.*)$/) {
			# source code files MUST have SPDX license declared
			ERROR("New file '" . $fileinfo->{filenew} .
			      "' requires 'SPDX-License-Identifier'");
		} else {
			# Other files MAY have SPDX license if appropriate
			WARN("Does new file '" . $fileinfo->{filenew} .
			     "' need 'SPDX-License-Identifier'?");
		}
	}
	if ($fileinfo->{action} eq "new" &&
	    exists $fileinfo->{facts}->{sawboilerplate}) {
		ERROR("New file '" . $fileinfo->{filenew} . "' must " .
		      "not have license boilerplate header text, only " .
		      "the SPDX-License-Identifier, unless this file was " .
		      "copied from existing code already having such text.");
	}
}

sub process {
	my $filename = shift;

	my $linenr=0;
	my $prevline="";
	my $prevrawline="";
	my $stashline="";
	my $stashrawline="";

	my $length;
	my $indent;
	my $previndent=0;
	my $stashindent=0;

	our $clean = 1;
	my $signoff = 0;
	my $is_patch = 0;

	my $in_header_lines = $file ? 0 : 1;
	my $in_commit_log = 0;		#Scanning lines before patch
	my $reported_mixing_imported_file = 0;
	my $in_imported_file = 0;
	my $in_no_imported_file = 0;
	my $non_utf8_charset = 0;

	our @report = ();
	our $cnt_lines = 0;
	our $cnt_error = 0;
	our $cnt_warn = 0;
	our $cnt_chk = 0;

	# Trace the real file/line as we go.
	my $realfile = '';
	my $realline = 0;
	my $realcnt = 0;
	my $fileinfo;
	my @fileinfolist;
	my $here = '';
	my $oldhere = '';
	my $in_comment = 0;
	my $comment_edge = 0;
	my $first_line = 0;
	my $p1_prefix = '';

	my $prev_values = 'E';

	# suppression flags
	my %suppress_ifbraces;
	my %suppress_whiletrailers;
	my %suppress_export;

	# Pre-scan the patch sanitizing the lines.

	sanitise_line_reset();
	my $line;
	foreach my $rawline (@rawlines) {
		$linenr++;
		$line = $rawline;

		if ($rawline=~/^\@\@ -\d+(?:,\d+)? \+(\d+)(,(\d+))? \@\@/) {
			$realline=$1-1;
			if (defined $2) {
				$realcnt=$3+1;
			} else {
				$realcnt=1+1;
			}
			$in_comment = 0;

			# Guestimate if this is a continuing comment.  Run
			# the context looking for a comment "edge".  If this
			# edge is a close comment then we must be in a comment
			# at context start.
			my $edge;
			my $cnt = $realcnt;
			for (my $ln = $linenr + 1; $cnt > 0; $ln++) {
				next if (defined $rawlines[$ln - 1] &&
					 $rawlines[$ln - 1] =~ /^-/);
				$cnt--;
				#print "RAW<$rawlines[$ln - 1]>\n";
				last if (!defined $rawlines[$ln - 1]);
				if ($rawlines[$ln - 1] =~ m@(/\*|\*/)@ &&
				    $rawlines[$ln - 1] !~ m@"[^"]*(?:/\*|\*/)[^"]*"@) {
					($edge) = $1;
					last;
				}
			}
			if (defined $edge && $edge eq '*/') {
				$in_comment = 1;
			}

			# 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 (!defined $edge &&
			    $rawlines[$linenr] =~ m@^.\s*(?:\*\*+| \*)(?:\s|$)@)
			{
				$in_comment = 1;
			}

			##print "COMMENT:$in_comment edge<$edge> $rawline\n";
			sanitise_line_reset($in_comment);

		} elsif ($realcnt && $rawline =~ /^(?:\+| |$)/) {
			# Standardise the strings and chars within the input to
			# simplify matching -- only bother with positive lines.
			$line = sanitise_line($rawline);
		}
		push(@lines, $line);

		if ($realcnt > 1) {
			$realcnt-- if ($line =~ /^(?:\+| |$)/);
		} else {
			$realcnt = 0;
		}

		#print "==>$rawline\n";
		#print "-->$line\n";
	}

	$prefix = '';

	$realcnt = 0;
	$linenr = 0;
	foreach my $line (@lines) {
		$linenr++;

		my $rawline = $rawlines[$linenr - 1];

#extract the line range in the file after the patch is applied
		if ($line=~/^\@\@ -\d+(?:,\d+)? \+(\d+)(,(\d+))? \@\@/) {
			$is_patch = 1;
			$first_line = $linenr + 1;
			$realline=$1-1;
			if (defined $2) {
				$realcnt=$3+1;
			} else {
				$realcnt=1+1;
			}
			annotate_reset();
			$prev_values = 'E';

			%suppress_ifbraces = ();
			%suppress_whiletrailers = ();
			%suppress_export = ();
			next;

# track the line number as we move through the hunk, note that
# new versions of GNU diff omit the leading space on completely
# blank context lines so we need to count that too.
		} elsif ($line =~ /^( |\+|$)/) {
			$realline++;
			$realcnt-- if ($realcnt != 0);

			# Measure the line length and indent.
			($length, $indent) = line_stats($rawline);

			# Track the previous line.
			($prevline, $stashline) = ($stashline, $line);
			($previndent, $stashindent) = ($stashindent, $indent);
			($prevrawline, $stashrawline) = ($stashrawline, $rawline);

			#warn "line<$line>\n";

		} elsif ($realcnt == 1) {
			$realcnt--;
		}

		my $hunk_line = ($realcnt != 0);

#make up the handle for any error we report on this line
		$prefix = "$filename:$realline: " if ($emacs && $file);
		$prefix = "$filename:$linenr: " if ($emacs && !$file);

		$oldhere = $here;
		$here = "#$linenr: " if (!$file);
		$here = "#$realline: " if ($file);

		# extract the filename as it passes
		if ($line =~ /^diff --git\s+(\S+)\s+(\S+)$/) {
			my $fileold = $1;
			my $filenew = $2;

			if (defined $fileinfo) {
				$fileinfo->{lineend} = $oldhere;
				process_end_of_file($fileinfo)
		        }
			$fileold =~ s@^([^/]*)/@@ if (!$file);
			$filenew =~ s@^([^/]*)/@@ if (!$file);
			$realfile = $filenew;

			$fileinfo = {
				"isgit" => 1,
				"githeader" => 1,
				"linestart" => $here,
				"lineend" => 0,
				"fileold" => $fileold,
				"filenew" => $filenew,
				"action" => "modified",
				"mode" => 0,
				"similarity" => 0,
				"facts" => {},
		        };
			push @fileinfolist, $fileinfo;
		} elsif (defined $fileinfo && $fileinfo->{githeader} &&
			 $line =~ /^(new|deleted) (?:file )?mode\s+([0-7]+)$/) {
			$fileinfo->{action} = $1;
			$fileinfo->{mode} = oct($2);
		} elsif (defined $fileinfo && $fileinfo->{githeader} &&
			 $line =~ /^similarity index (\d+)%/) {
			$fileinfo->{similarity} = int($1);
		} elsif (defined $fileinfo && $fileinfo->{githeader} &&
			 $line =~ /^rename (from|to) [\w\/\.\-]+\s*$/) {
			$fileinfo->{action} = "renamed";
			# For a no-change rename, we'll never have any "+++..."
			# lines, so trigger actions now
			if ($1 eq "to" && $fileinfo->{similarity} == 100)  {
				process_start_of_file($fileinfo);
			}
		} elsif ($line =~ /^\+\+\+\s+(\S+)/) {
			$realfile = $1;
			$realfile =~ s@^([^/]*)/@@ if (!$file);

			$p1_prefix = $1;
			if (!$file && $tree && $p1_prefix ne '' &&
			    -e "$root/$p1_prefix") {
				WARN("patch prefix '$p1_prefix' exists, appears to be a -p0 patch\n");
			}

			if (defined $fileinfo && !$fileinfo->{isgit}) {
				$fileinfo->{lineend} = $oldhere;
				process_end_of_file($fileinfo);
			}

			if (!defined $fileinfo || !$fileinfo->{isgit}) {
				$fileinfo = {
					"isgit" => 0,
					"githeader" => 0,
					"linestart" => $here,
					"lineend" => 0,
					"fileold" => $realfile,
					"filenew" => $realfile,
					"action" => "modified",
					"mode" => 0,
					"similarity" => 0,
					"facts" => {},
			        };
				push @fileinfolist, $fileinfo;
			} else {
				$fileinfo->{githeader} = 0;
			}
			process_start_of_file($fileinfo);

			next;
		}

		$here .= "FILE: $realfile:$realline:" if ($realcnt != 0);

		my $hereline = "$here\n$rawline\n";
		my $herecurr = "$here\n$rawline\n";
		my $hereprev = "$here\n$prevrawline\n$rawline\n";

		$cnt_lines++ if ($realcnt != 0);

# Only allow Python 3 interpreter
		if ($realline == 1 &&
			$line =~ /^\+#!\ *\/usr\/bin\/(?:env )?python$/) {
			ERROR("please use python3 interpreter\n" . $herecurr);
		}

# Accept git diff extended headers as valid patches
		if ($line =~ /^(?:rename|copy) (?:from|to) [\w\/\.\-]+\s*$/) {
			$is_patch = 1;
		}

		if ($line =~ /^(Author|From): .* via .*<qemu-\w+\@nongnu\.org>/) {
		    ERROR("Author email address is mangled by the mailing list\n" . $herecurr);
		}

#check the patch for a signoff:
		if ($line =~ /^\s*signed-off-by:/i) {
			# This is a signoff, if ugly, so do not double report.
			$signoff++;
			$in_commit_log = 0;

			if (!($line =~ /^\s*Signed-off-by:/)) {
				ERROR("The correct form is \"Signed-off-by\"\n" .
					$herecurr);
			}
			if ($line =~ /^\s*signed-off-by:\S/i) {
				ERROR("space required after Signed-off-by:\n" .
					$herecurr);
			}
		}

# Check SPDX-License-Identifier references a permitted license
		if ($rawline =~ m,SPDX-License-Identifier: (.*?)(\*/)?\s*$,) {
			$fileinfo->{facts}->{sawspdx} = 1;
			&checkspdx($realfile, $1);
		}

		if ($rawline =~ /$LICENSE_BOILERPLATE_RE/) {
			$fileinfo->{facts}->{sawboilerplate} = 1;
		}

		if ($rawline =~ m,(SPDX-[a-zA-Z0-9-_]+):,) {
			my $tag = $1;
			my @permitted = qw(
				SPDX-License-Identifier
			);

			unless (grep { /^$tag$/ } @permitted) {
			    ERROR("Tag $tag not permitted in QEMU code, " .
				  "valid choices are: " .
				  join(", ", @permitted));
			}
		}

# Check for wrappage within a valid hunk of the file
		if ($realcnt != 0 && $line !~ m{^(?:\+|-| |\\ No newline|$)}) {
			ERROR("patch seems to be corrupt (line wrapped?)\n" .
				$herecurr) if (!$emitted_corrupt++);
		}

# UTF-8 regex found at http://www.w3.org/International/questions/qa-forms-utf-8.en.php
		if (($realfile =~ /^$/ || $line =~ /^\+/) &&
		    $rawline !~ m/^$UTF8*$/) {
			my ($utf8_prefix) = ($rawline =~ /^($UTF8*)/);

			my $blank = copy_spacing($rawline);
			my $ptr = substr($blank, 0, length($utf8_prefix)) . "^";
			my $hereptr = "$hereline$ptr\n";

			ERROR("Invalid UTF-8, patch and commit message should be encoded in UTF-8\n" . $hereptr);
		}

		if ($rawline =~ m/$UTF8_MOJIBAKE/) {
			ERROR("Doubly-encoded UTF-8\n" . $herecurr);
		}
# Check if it's the start of a commit log
# (not a header line and we haven't seen the patch filename)
		if ($in_header_lines && $realfile =~ /^$/ &&
		    !($rawline =~ /^\s+\S/ ||
		      $rawline =~ /^(commit\b|from\b|[\w-]+:).*$/i)) {
			$in_header_lines = 0;
			$in_commit_log = 1;
		}

# Check if there is UTF-8 in a commit log when a mail header has explicitly
# declined it, i.e defined some charset where it is missing.
		if ($in_header_lines &&
		    $rawline =~ /^Content-Type:.+charset="(.+)".*$/ &&
		    $1 !~ /utf-8/i) {
			$non_utf8_charset = 1;
		}

		if ($in_commit_log && $non_utf8_charset && $realfile =~ /^$/ &&
		    $rawline =~ /$NON_ASCII_UTF8/) {
			WARN("8-bit UTF-8 used in possible commit log\n" . $herecurr);
		}

# Check for various typo / spelling mistakes
		if (defined($misspellings) &&
		    ($in_commit_log || $line =~ /^(?:\+|Subject:)/i)) {
			while ($rawline =~ /(?:^|[^\w\-'`])($misspellings)(?:[^\w\-'`]|$)/gi) {
				my $typo = $1;
				my $blank = copy_spacing($rawline);
				my $ptr = substr($blank, 0, $-[1]) . "^" x length($typo);
				my $hereptr = "$hereline$ptr\n";
				my $typo_fix = $spelling_fix{lc($typo)};
				$typo_fix = ucfirst($typo_fix) if ($typo =~ /^[A-Z]/);
				$typo_fix = uc($typo_fix) if ($typo =~ /^[A-Z]+$/);
				WARN("'$typo' may be misspelled - perhaps '$typo_fix'?\n" . $hereptr);
			}
		}

# ignore non-hunk lines and lines being removed
		next if (!$hunk_line || $line =~ /^-/);

# Check that updating imported files from Linux are not mixed with other changes
		if ($realfile =~ /^(linux-headers|include\/standard-headers)\//) {
			if (!$in_imported_file) {
				WARN("added, moved or deleted file(s) " .
				     "imported from Linux, are you using " .
				     "scripts/update-linux-headers.sh?\n" .
				     $herecurr);
			}
			$in_imported_file = 1;
		} else {
			$in_no_imported_file = 1;
		}

		if (!$reported_mixing_imported_file &&
		    $in_imported_file && $in_no_imported_file) {
			ERROR("headers imported from Linux should be self-" .
			      "contained in a patch with no other changes\n" .
			      $herecurr);
			$reported_mixing_imported_file = 1;
		}

# ignore files that are being periodically imported from Linux
		next if ($realfile =~ /^(linux-headers|include\/standard-headers)\//);

#trailing whitespace
		if ($line =~ /^\+.*\015/) {
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			ERROR("DOS line endings\n" . $herevet);

		} elsif ($realfile =~ /^docs\/.+\.txt/ ||
			 $realfile =~ /^docs\/.+\.md/) {
		    if ($rawline =~ /^\+\s+$/ && $rawline !~ /^\+ {4}$/) {
			# TODO: properly check we're in a code block
			#       (surrounding text is 4-column aligned)
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			ERROR("code blocks in documentation should have " .
			      "empty lines with exactly 4 columns of " .
			      "whitespace\n" . $herevet);
		    }
		} elsif ($rawline =~ /^\+.*\S\s+$/ || $rawline =~ /^\+\s+$/) {
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			ERROR("trailing whitespace\n" . $herevet);
			$rpt_cleaners = 1;
		}

# checks for trace-events files
		if ($realfile =~ /trace-events$/ && $line =~ /^\+/) {
			if ($rawline =~ /%[-+ 0]*#/) {
				ERROR("Don't use '#' flag of printf format ('%#') in " .
				      "trace-events, use '0x' prefix instead\n" . $herecurr);
			} else {
				my $hex =
					qr/%[-+ *.0-9]*([hljztL]|ll|hh)?(x|X|"\s*PRI[xX][^"]*"?)/;

				# don't consider groups split by [.:/ ], like 2A.20:12ab
				my $tmpline = $rawline;
				$tmpline =~ s/($hex[.:\/ ])+$hex//g;

				if ($tmpline =~ /(?<!0x)$hex/) {
					ERROR("Hex numbers must be prefixed with '0x'\n" .
					      $herecurr);
				}
			}
		}

# check we are in a valid source file if not then ignore this hunk
		next if ($realfile !~ /$SrcFile/);

#90 column limit; exempt URLs, if no other words on line
		if ($line =~ /^\+/ &&
		    !($line =~ /^\+\s*"[^"]*"\s*(?:\s*|,|\)\s*;)\s*$/) &&
		    !($rawline =~ /^[^[:alnum:]]*https?:\S*$/) &&
		    $length > 80)
		{
			if ($length > 90) {
				ERROR("line over 90 characters\n" . $herecurr);
			} else {
				WARN("line over 80 characters\n" . $herecurr);
			}
		}

# check for spaces before a quoted newline
		if ($rawline =~ /^.*\".*\s\\n/) {
			ERROR("unnecessary whitespace before a quoted newline\n" . $herecurr);
		}

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

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

# tabs are only allowed in assembly source code, and in
# some scripts we imported from other projects.
		next if ($realfile =~ /\.(s|S)$/);
		next if ($realfile =~ /(checkpatch|get_maintainer)\.pl$/);
		next if ($realfile =~ /^target\/hexagon\/imported\/*/);

		if ($rawline =~ /^\+.*\t/) {
			my $herevet = "$here\n" . cat_vet($rawline) . "\n";
			ERROR("code indent should never use tabs\n" . $herevet);
			$rpt_cleaners = 1;
		}

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

# Block comment styles

		# Block comments use /* on a line of its own
		my $commentline = $rawline;
		while ($commentline =~ s@^(\+.*)/\*.*\*/@$1@o) { # remove inline /*...*/
		}
		if ($commentline =~ m@^\+.*/\*\*?+[ \t]*[^ \t]@) { # /* or /** non-blank
			WARN("Block comments use a leading /* on a separate line\n" . $herecurr);
		}

# Block comments use * on subsequent lines
		if ($prevline =~ /$;[ \t]*$/ &&			#ends in comment
		    $prevrawline =~ /^\+.*?\/\*/ &&		#starting /*
		    $prevrawline !~ /\*\/[ \t]*$/ &&		#no trailing */
		    $rawline =~ /^\+/ &&			#line is new
		    $rawline !~ /^\+[ \t]*\*/) {		#no leading *
			WARN("Block comments use * on subsequent lines\n" . $hereprev);
		}

# Block comments use */ on trailing lines
		if ($rawline !~ m@^\+[ \t]*\*/[ \t]*$@ &&	#trailing */
		    $rawline !~ m@^\+.*/\*.*\*/[ \t]*$@ &&	#inline /*...*/
		    $rawline !~ m@^\+.*\*{2,}/[ \t]*$@ &&	#trailing **/
		    $rawline =~ m@^\+[ \t]*.+\*\/[ \t]*$@) {	#non blank */
			WARN("Block comments use a trailing */ on a separate line\n" . $herecurr);
		}

# Block comment * alignment
		if ($prevline =~ /$;[ \t]*$/ &&			#ends in comment
		    $line =~ /^\+[ \t]*$;/ &&			#leading comment
		    $rawline =~ /^\+[ \t]*\*/ &&		#leading *
		    (($prevrawline =~ /^\+.*?\/\*/ &&		#leading /*
		      $prevrawline !~ /\*\/[ \t]*$/) ||		#no trailing */
		     $prevrawline =~ /^\+[ \t]*\*/)) {		#leading *
			my $oldindent;
			$prevrawline =~ m@^\+([ \t]*/?)\*@;
			if (defined($1)) {
				$oldindent = expand_tabs($1);
			} else {
				$prevrawline =~ m@^\+(.*/?)\*@;
				$oldindent = expand_tabs($1);
			}
			$rawline =~ m@^\+([ \t]*)\*@;
			my $newindent = $1;
			$newindent = expand_tabs($newindent);
			if (length($oldindent) ne length($newindent)) {
				WARN("Block comments should align the * on each line\n" . $hereprev);
			}
		}

# Check for potential 'bare' types
		my ($stat, $cond, $line_nr_next, $remain_next, $off_next,
		    $realline_next);
		if ($realcnt && $line =~ /.\s*\S/) {
			($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;

			# 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 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);
			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";

			# The length of the "previous line" is checked against 80 because it
			# includes the + at the beginning of the line (if the actual line has
			# 79 or 80 characters, it is no longer possible to add a space and an
			# opening brace there)
			if ($#ctx == 0 && $ctx !~ /{\s*/ &&
			    defined($lines[$ctx_ln - 1]) && $lines[$ctx_ln - 1] =~ /^\+\s*\{/ &&
			    defined($lines[$ctx_ln - 2]) && length($lines[$ctx_ln - 2]) < 80) {
				ERROR("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 > $indent) {
					ERROR("trailing semicolon indicates no statements, indent implies otherwise\n" .
						"$here\n$ctx\n$rawlines[$ctx_ln - 1]\n");
				}
			}
		}

# 'do ... while (0/false)' only makes sense in macros, without trailing ';'
		if ($line =~ /while\s*\((0|false)\);/) {
			ERROR("suspicious ; after while (0)\n" . $herecurr);
		}

# Check superfluous trailing ';'
		if ($line =~ /;;$/) {
			ERROR("superfluous trailing semicolon\n" . $herecurr);
		}

# Check relative indent for conditionals and blocks.
		if ($line =~ /\b(?:(?:if|while|for)\s*\(|do\b)/ && $line !~ /^.\s*#/ && $line !~ /\}\s*while\s*/) {
			my ($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 re-add 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 % 4) != 0 ||
			    ($sindent <= $indent && $s ne ''))) {
				ERROR("suspect code indent for conditional statements ($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
		if ($line=~/^[^\+]/) {next;}

# TEST: allow direct testing of the type matcher.
		if ($dbg_type) {
			if ($line =~ /^.\s*$Declare\s*$/) {
				ERROR("TEST: is type\n" . $herecurr);
			} elsif ($dbg_type > 1 && $line =~ /^.+($Declare)/) {
				ERROR("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: is attr\n" . $herecurr);
			} elsif ($dbg_attr > 1 && $line =~ /^.+($Modifier)/) {
				ERROR("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("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 filename\n" .
					$herecurr);
			}
		}

# no C99 // comments
		if ($line =~ m{//} &&
		    $rawline !~ m{// SPDX-License-Identifier: }) {
			ERROR("do not use C99 // comments\n" . $herecurr);
		}
		# Remove C99 comments.
		$line =~ s@//.*@@;
		$opline =~ s@//.*@@;

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

# * goes on variable not on type
		# (char*[ const])
		if ($line =~ m{\($NonptrType(\s*(?:$Modifier\b\s*|\*\s*)+)\)}) {
			my ($from, $to) = ($1, $1);

			# 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 "from<$from> to<$to>\n";
			if ($from ne $to) {
				ERROR("\"(foo$from)\" should be \"(foo$to)\"\n" .  $herecurr);
			}
		} elsif ($line =~ m{\b$NonptrType(\s*(?:$Modifier\b\s*|\*\s*)+)($Ident)}) {
			my ($from, $to, $ident) = ($1, $1, $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+\*/\*\*/) {
			}
			# Modifiers should have spaces.
			$to =~ s/(\b$Modifier$)/$1 /;

			#print "from<$from> to<$to> ident<$ident>\n";
			if ($from ne $to && $ident !~ /^$Modifier$/) {
				ERROR("\"foo${from}bar\" should be \"foo${to}bar\"\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 '{' 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 '{' 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)?(?:\s+$Ident)?[=\{]/) {
			ERROR("missing space after $1 definition\n" . $herecurr);
		}

# 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 }
#  4. after a comma -- [1] = 5, [2] = 6
#  5. in a macro definition -- #define abc(x) [x] = y
		while ($line =~ /(.*?\s)\[/g) {
			my ($where, $prefix) = ($-[1], $1);
			if ($prefix !~ /$Type\s+$/ &&
			    ($where != 0 || $prefix !~ /^.\s+$/) &&
			    $prefix !~ /\#\s*define[^(]*\([^)]*\)\s+$/ &&
			    $prefix !~ /[,{:]\s+$/) {
				ERROR("space prohibited before open square bracket '['\n" . $herecurr);
			}
		}

# 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 ($name =~ /^(?:
				if|for|while|switch|return|case|
				volatile|__volatile__|coroutine_fn|
				__attribute__|format|__extension__|
				asm|__asm__)$/x)
			{

			# Ignore 'catch (...)' in C++
			} elsif ($name =~ /^catch$/ && $realfile =~ /(\.cpp|\.h)$/) {

			# 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 {
				ERROR("space prohibited between function name and open parenthesis '('\n" . $herecurr);
			}
		}
# Check operator spacing.
		if (!($line=~/\#\s*(include|import)/)) {
			my $ops = qr{
				<<=|>>=|<=|>=|==|!=|
				\+=|-=|\*=|\/=|%=|\^=|\|=|&=|
				=>|->|<<|>>|<|>|=|!|~|
				&&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/|%|
				\?|::|:
			}x;
			my @elements = split(/($ops|;)/, $opline);
			my $off = 0;

			my $blank = copy_spacing($opline);

			for (my $n = 0; $n < $#elements; $n += 2) {
				$off += length($elements[$n]);

				# Pick up the preceding and succeeding characters.
				my $ca = substr($opline, 0, $off);
				my $cc = '';
				if (length($opline) >= ($off + length($elements[$n + 1]))) {
					$cc = substr($opline, $off + length($elements[$n + 1]));
				}
				my $cb = "$ca$;$cc";

				my $a = '';
				$a = 'V' if ($elements[$n] ne '');
				$a = 'W' if ($elements[$n] =~ /\s$/);
				$a = 'C' if ($elements[$n] =~ /$;$/);
				$a = 'B' if ($elements[$n] =~ /(\[|\()$/);
				$a = 'O' if ($elements[$n] eq '');
				$a = 'E' if ($ca =~ /^\s*$/);

				my $op = $elements[$n + 1];

				my $c = '';
				if (defined $elements[$n + 2]) {
					$c = 'V' if ($elements[$n + 2] ne '');
					$c = 'W' if ($elements[$n + 2] =~ /^\s/);
					$c = 'C' if ($elements[$n + 2] =~ /^$;/);
					$c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
					$c = 'O' if ($elements[$n + 2] eq '');
					$c = 'E' if ($elements[$n + 2] =~ /^\s*\\$/);
				} else {
					$c = 'E';
				}

				my $ctx = "${a}x${c}";

				my $at = "(ctx:$ctx)";

				my $ptr = substr($blank, 0, $off) . "^";
				my $hereptr = "$hereline$ptr\n";

				# Pull out the value of this operator.
				my $op_type = substr($curr_values, $off + 1, 1);

				# Get the full operator variant.
				my $opv = $op . substr($curr_vars, $off, 1);

				# Ignore operators passed as parameters.
				if ($op_type ne 'V' &&
				    $ca =~ /\s$/ && $cc =~ /^\s*,/) {

#				# Ignore comments
#				} elsif ($op =~ /^$;+$/) {

				# ; should have either the end of line or a space or \ after it
				} elsif ($op eq ';') {
					if ($ctx !~ /.x[WEBC]/ &&
					    $cc !~ /^\\/ && $cc !~ /^;/) {
						ERROR("space required after that '$op' $at\n" . $hereptr);
					}

				# // is a comment
				} elsif ($op eq '//') {

				# Ignore : used in class declaration in C++
				} elsif ($opv eq ':B' && $ctx =~ /Wx[WE]/ &&
						 $line =~ /class/ && $realfile =~ /(\.cpp|\.h)$/) {

				# No spaces for:
				#   ->
				#   :   when part of a bitfield
				} elsif ($op eq '->' || $opv eq ':B') {
					if ($ctx =~ /Wx.|.xW/) {
						ERROR("spaces prohibited around that '$op' $at\n" . $hereptr);
					}

				# , must have a space on the right.
                                # not required when having a single },{ on one line
				} elsif ($op eq ',') {
					if ($ctx !~ /.x[WEC]/ && $cc !~ /^}/ &&
                                            ($elements[$n] . $elements[$n + 2]) !~ " *}\\{") {
						ERROR("space required after that '$op' $at\n" . $hereptr);
					}

				# '*' as part of a type definition -- reported already.
				} elsif ($opv eq '*_') {
					#warn "'*' is part of type\n";

				# unary operators should have a space before and
				# none after.  May be left adjacent to another
				# unary operator, or a cast
				} elsif ($op eq '!' || $op eq '~' ||
					 $opv eq '*U' || $opv eq '-U' ||
					 $opv eq '&U' || $opv eq '&&U') {
					if ($op eq '~' && $ca =~ /::$/ && $realfile =~ /(\.cpp|\.h)$/) {
						# '~' used as a name of Destructor

					} elsif ($ctx !~ /[WEBC]x./ && $ca !~ /(?:\)|!|~|\*|-|\&|\||\+\+|\-\-|\{)$/) {
						ERROR("space required before that '$op' $at\n" . $hereptr);
					}
					if ($op eq '*' && $cc =~/\s*$Modifier\b/) {
						# A unary '*' may be const

					} elsif ($ctx =~ /.xW/) {
						ERROR("space prohibited after that '$op' $at\n" . $hereptr);
					}

				# unary ++ and unary -- are allowed no space on one side.
				} elsif ($op eq '++' or $op eq '--') {
					if ($ctx !~ /[WEOBC]x[^W]/ && $ctx !~ /[^W]x[WOBEC]/) {
						ERROR("space required one side of that '$op' $at\n" . $hereptr);
					}
					if ($ctx =~ /Wx[BE]/ ||
					    ($ctx =~ /Wx./ && $cc =~ /^;/)) {
						ERROR("space prohibited before that '$op' $at\n" . $hereptr);
					}
					if ($ctx =~ /ExW/) {
						ERROR("space prohibited after that '$op' $at\n" . $hereptr);
					}

				# A colon needs no spaces before when it is
				# terminating a case value or a label.
				} elsif ($opv eq ':C' || $opv eq ':L') {
					if ($ctx =~ /Wx./) {
						ERROR("space prohibited before that '$op' $at\n" . $hereptr);
					}

				# All the others need spaces both sides.
				} elsif ($ctx !~ /[EWC]x[CWE]/) {
					my $ok = 0;

					if ($realfile =~ /\.cpp|\.h$/) {
						# Ignore template arguments <...> in C++
						if (($op eq '<' || $op eq '>') && $line =~ /<.*>/) {
							$ok = 1;
						}

						# Ignore :: in C++
						if ($op eq '::') {
							$ok = 1;
						}
					}

					# Ignore email addresses <foo@bar>
					if (($op eq '<' &&
					     $cc =~ /^\S+\@\S+>/) ||
					    ($op eq '>' &&
					     $ca =~ /<\S+\@\S+$/))
					{
						$ok = 1;
					}

					# Ignore ?:
					if (($opv eq ':O' && $ca =~ /\?$/) ||
					    ($op eq '?' && $cc =~ /^:/)) {
						$ok = 1;
					}

					if ($ok == 0) {
						ERROR("spaces required around that '$op' $at\n" . $hereptr);
					}
				}
				$off += length($elements[$n + 1]);
			}
		}

#need space before brace following if, while, etc
		if (($line =~ /\(.*\)\{/ && $line !~ /\($Type\)\{/) ||
		    $line =~ /do\{/) {
			ERROR("space required before the open brace '{'\n" . $herecurr);
		}

# closing brace should have a space following it when it has anything
# on the line
		if ($line =~ /}(?!(?:,|;|\)))\S/) {
			ERROR("space required after that close brace '}'\n" . $herecurr);
		}

# check spacing on square brackets
		if ($line =~ /\[\s/ && $line !~ /\[\s*$/) {
			ERROR("space prohibited after that open square bracket '['\n" . $herecurr);
		}
		if ($line =~ /\s\]/) {
			ERROR("space prohibited before that close square bracket ']'\n" . $herecurr);
		}

# check spacing on parentheses
		if ($line =~ /\(\s/ && $line !~ /\(\s*(?:\\)?$/ &&
		    $line !~ /for\s*\(\s+;/) {
			ERROR("space prohibited after that open parenthesis '('\n" . $herecurr);
		}
		if ($line =~ /(\s+)\)/ && $line !~ /^.\s*\)/ &&
		    $line !~ /for\s*\(.*;\s+\)/ &&
		    $line !~ /:\s+\)/) {
			ERROR("space prohibited before that close parenthesis ')'\n" . $herecurr);
		}

# Return is not a function.
		if (defined($stat) && $stat =~ /^.\s*return(\s*)(\(.*);/s) {
			my $spacing = $1;
			my $value = $2;

			# Flatten any parentheses
			$value =~ s/\(/ \(/g;
			$value =~ s/\)/\) /g;
			while ($value =~ s/\[[^\{\}]*\]/1/ ||
			       $value !~ /(?:$Ident|-?$Constant)\s*
					     $Compare\s*
					     (?:$Ident|-?$Constant)/x &&
			       $value =~ s/\([^\(\)]*\)/1/) {
			}
#print "value<$value>\n";
			if ($value =~ /^\s*(?:$Ident|-?$Constant)\s*$/ &&
			    $line =~ /;$/) {
				ERROR("return is not a function, parentheses are not required\n" . $herecurr);

			} elsif ($spacing !~ /\s+/) {
				ERROR("space required before the open parenthesis '('\n" . $herecurr);
			}
		}
# Return of what appears to be an errno should normally be -'ve
		if ($line =~ /^.\s*return\s*(E[A-Z]*)\s*;/) {
			my $name = $1;
			if ($name ne 'EOF' && $name ne 'ERROR') {
				ERROR("return of an errno should typically be -ve (return -$1)\n" . $herecurr);
			}
		}

		if ($line =~ /^.\s*(Q(?:S?LIST|SIMPLEQ|TAILQ)_HEAD)\s*\(\s*[^,]/ &&
		    $line !~ /^.typedef/) {
			ERROR("named $1 should be typedefed separately\n" . $herecurr);
		}

# Need a space before open parenthesis after if, while etc
		if ($line=~/\b(if|while|for|switch)\(/) {
			ERROR("space required before the open parenthesis '('\n" . $herecurr);
		}

# Check for illegal assignment in if conditional -- and check for trailing
# statements after the conditional.
		if ($line =~ /do\s*(?!{)/) {
			my ($stat_next) = ctx_statement_block($line_nr_next,
						$remain_next, $off_next);
			$stat_next =~ s/\n./\n /g;
			##print "stat<$stat> stat_next<$stat_next>\n";

			if ($stat_next =~ /^\s*while\b/) {
				# If the statement carries leading newlines,
				# then count those as offsets.
				my ($whitespace) =
					($stat_next =~ /^((?:\s*\n[+-])*\s*)/s);
				my $offset =
					statement_rawlines($whitespace) - 1;

				$suppress_whiletrailers{$line_nr_next +
								$offset} = 1;
			}
		}
		if (!defined $suppress_whiletrailers{$linenr} &&
		    $line =~ /\b(?:if|while|for)\s*\(/ && $line !~ /^.\s*#/) {
			my ($s, $c) = ($stat, $cond);

			if ($c =~ /\bif\s*\(.*[^<>!=]=[^=].*/s) {
				ERROR("do not use assignment in if condition\n" . $herecurr);
			}

			# Find out what is on the end of the line after the
			# conditional.
			substr($s, 0, length($c), '');
			$s =~ s/\n.*//g;
			$s =~ s/$;//g; 	# Remove any comments
			if (length($c) && $s !~ /^\s*{?\s*\\*\s*$/ &&
			    $c !~ /}\s*while\s*/)
			{
				# Find out how long the conditional actually is.
				my @newlines = ($c =~ /\n/gs);
				my $cond_lines = 1 + $#newlines;
				my $stat_real = '';

				$stat_real = raw_line($linenr, $cond_lines)
							. "\n" if ($cond_lines);
				if (defined($stat_real) && $cond_lines > 1) {
					$stat_real = "[...]\n$stat_real";
				}

				ERROR("trailing statements should be on next line\n" . $herecurr . $stat_real);
			}
		}

# Check for bitwise tests written as boolean
		if ($line =~ /
			(?:
				(?:\[|\(|\&\&|\|\|)
				\s*0[xX][0-9]+\s*
				(?:\&\&|\|\|)
			|
				(?:\&\&|\|\|)
				\s*0[xX][0-9]+\s*
				(?:\&\&|\|\||\)|\])
			)/x)
		{
			ERROR("boolean test with hexadecimal, perhaps just 1 \& or \|?\n" . $herecurr);
		}

# if and else should not have general statements after it
		if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/) {
			my $s = $1;
			$s =~ s/$;//g; 	# Remove any comments
			if ($s !~ /^\s*(?:\sif|(?:{|)\s*\\?\s*$)/) {
				ERROR("trailing statements should be on next line\n" . $herecurr);
			}
		}
# if should not continue a brace
		if ($line =~ /}\s*if\b/) {
			ERROR("trailing statements should be on next line\n" .
				$herecurr);
		}
# case and default should not have general statements after them
		if ($line =~ /^.\s*(?:case\s*.*|default\s*):/g &&
		    $line !~ /\G(?:
			(?:\s*$;*)(?:\s*{)?(?:\s*$;*)(?:\s*\\)?\s*$|
			\s*return\s+
		    )/xg)
		{
			ERROR("trailing statements should be on next line\n" . $herecurr);
		}

		# 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) {
			ERROR("else should follow close brace '}'\n" . $hereprev);
		}

		if ($prevline=~/}\s*$/ and $line=~/^.\s*while\s*/ and
						$previndent == $indent) {
			my ($s, $c) = ctx_statement_block($linenr, $realcnt, 0);

			# Find out what is on the end of the line after the
			# conditional.
			substr($s, 0, length($c), '');
			$s =~ s/\n.*//g;

			if ($s =~ /^\s*;/) {
				ERROR("while should follow close brace '}'\n" . $hereprev);
			}
		}

#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 ($line=~/\#\s*define.*\\\s$/) {
			ERROR("Whitespace after \\ makes next lines useless\n" . $herecurr);
		}

# multi-statement macros should be enclosed in a do while loop, grab the
# first statement and ensure its the whole macro if its not enclosed
# in a known good container
		if ($realfile !~ m@/vmlinux.lds.h$@ &&
		    $line =~ /^.\s*\#\s*define\s*$Ident(\()?/) {
			my $ln = $linenr;
			my $cnt = $realcnt;
			my ($off, $dstat, $dcond, $rest);
			my $ctx = '';

			my $args = defined($1);

			# Find the end of the macro and limit our statement
			# search to that.
			while ($cnt > 0 && defined $lines[$ln - 1] &&
				$lines[$ln - 1] =~ /^(?:-|..*\\$)/)
			{
				$ctx .= $rawlines[$ln - 1] . "\n";
				$cnt-- if ($lines[$ln - 1] !~ /^-/);
				$ln++;
			}
			$ctx .= $rawlines[$ln - 1];

			($dstat, $dcond, $ln, $cnt, $off) =
				ctx_statement_block($linenr, $ln - $linenr + 1, 0);
			#print "dstat<$dstat> dcond<$dcond> cnt<$cnt> off<$off>\n";
			#print "LINE<$lines[$ln-1]> len<" . length($lines[$ln-1]) . "\n";

			# Extract the remainder of the define (if any) and
			# rip off surrounding spaces, and trailing \'s.
			$rest = '';
			while ($off != 0 || ($cnt > 0 && $rest =~ /\\\s*$/)) {
				#print "ADDING cnt<$cnt> $off <" . substr($lines[$ln - 1], $off) . "> rest<$rest>\n";
				if ($off != 0 || $lines[$ln - 1] !~ /^-/) {
					$rest .= substr($lines[$ln - 1], $off) . "\n";
					$cnt--;
				}
				$ln++;
				$off = 0;
			}
			$rest =~ s/\\\n.//g;
			$rest =~ s/^\s*//s;
			$rest =~ s/\s*$//s;

			# Clean up the original statement.
			if ($args) {
				substr($dstat, 0, length($dcond), '');
			} else {
				$dstat =~ s/^.\s*\#\s*define\s+$Ident\s*//;
			}
			$dstat =~ s/$;//g;
			$dstat =~ s/\\\n.//g;
			$dstat =~ s/^\s*//s;
			$dstat =~ s/\s*$//s;

			# Flatten any parentheses and braces
			while ($dstat =~ s/\([^\(\)]*\)/1/ ||
			       $dstat =~ s/\{[^\{\}]*\}/1/ ||
			       $dstat =~ s/\[[^\{\}]*\]/1/)
			{
			}

			my $exceptions = qr{
				$Declare|
				module_param_named|
				MODULE_PARAM_DESC|
				DECLARE_PER_CPU|
				DEFINE_PER_CPU|
				__typeof__\(|
				union|
				struct|
				\.$Ident\s*=\s*|
				^\"|\"$
			}x;
			#print "REST<$rest> dstat<$dstat> ctx<$ctx>\n";
			if ($rest ne '' && $rest ne ',') {
				if ($rest !~ /while\s*\(/ &&
				    $dstat !~ /$exceptions/)
				{
					ERROR("Macros with multiple statements should be enclosed in a do - while loop\n" . "$here\n$ctx\n");
				}

			} elsif ($ctx !~ /;/) {
				if ($dstat ne '' &&
				    $dstat !~ /^(?:$Ident|-?$Constant)$/ &&
				    $dstat !~ /$exceptions/ &&
				    $dstat !~ /^\.$Ident\s*=/ &&
				    $dstat =~ /$Operators/)
				{
					ERROR("Macros with complex values should be enclosed in parenthesis\n" . "$here\n$ctx\n");
				}
			}
		}

# check for missing bracing around if etc
		if ($line =~ /(^.*)\b(?:if|while|for)\b/ &&
			$line !~ /\#\s*if/) {
			my $allowed = 0;

			# Check the pre-context.
			if ($line =~ /(\}.*?)$/) {
				my $pre = $1;

				if ($line !~ /else/) {
					print "APW: ALLOWED: pre<$pre> line<$line>\n"
						if $dbg_adv_apw;
					$allowed = 1;
				}
			}
			my ($level, $endln, @chunks) =
				ctx_statement_full($linenr, $realcnt, 1);
                        if ($dbg_adv_apw) {
                            print "APW: chunks<$#chunks> linenr<$linenr> endln<$endln> level<$level>\n";
                            print "APW: <<$chunks[1][0]>><<$chunks[1][1]>>\n"
                                if $#chunks >= 1;
                        }
			if ($#chunks >= 0 && $level == 0) {
				my $seen = 0;
				my $herectx = $here . "\n";
				my $ln = $linenr - 1;
				for my $chunk (@chunks) {
					my ($cond, $block) = @{$chunk};

					# If the condition carries leading newlines, then count those as offsets.
					my ($whitespace) = ($cond =~ /^((?:\s*\n[+-])*\s*)/s);
					my $offset = statement_rawlines($whitespace) - 1;

					#print "COND<$cond> whitespace<$whitespace> offset<$offset>\n";

					# We have looked at and allowed this specific line.
					$suppress_ifbraces{$ln + $offset} = 1;

					$herectx .= "$rawlines[$ln + $offset]\n[...]\n";
					$ln += statement_rawlines($block) - 1;

					substr($block, 0, length($cond), '');

					my $spaced_block = $block;
					$spaced_block =~ s/\n\+/ /g;

					$seen++ if ($spaced_block =~ /^\s*\{/);

                                        print "APW: cond<$cond> block<$block> allowed<$allowed>\n"
                                            if $dbg_adv_apw;
					if (statement_lines($cond) > 1) {
                                            print "APW: ALLOWED: cond<$cond>\n"
                                                if $dbg_adv_apw;
                                            $allowed = 1;
					}
					if ($block =~/\b(?:if|for|while)\b/) {
                                            print "APW: ALLOWED: block<$block>\n"
                                                if $dbg_adv_apw;
                                            $allowed = 1;
					}
					if (statement_block_size($block) > 1) {
                                            print "APW: ALLOWED: lines block<$block>\n"
                                                if $dbg_adv_apw;
                                            $allowed = 1;
					}
				}
				if ($seen != ($#chunks + 1) && !$allowed) {
					ERROR("braces {} are necessary for all arms of this statement\n" . $herectx);
				}
			}
		}
		if (!defined $suppress_ifbraces{$linenr - 1} &&
					$line =~ /\b(if|while|for|else)\b/ &&
					$line !~ /\#\s*if/ &&
					$line !~ /\#\s*else/) {
			my $allowed = 0;

                        # Check the pre-context.
                        if (substr($line, 0, $-[0]) =~ /(\}\s*)$/) {
                            my $pre = $1;

                            if ($line !~ /else/) {
                                print "APW: ALLOWED: pre<$pre> line<$line>\n"
                                    if $dbg_adv_apw;
                                $allowed = 1;
                            }
                        }

			my ($level, $endln, @chunks) =
				ctx_statement_full($linenr, $realcnt, $-[0]);

			# Check the condition.
			my ($cond, $block) = @{$chunks[0]};
                        print "CHECKING<$linenr> cond<$cond> block<$block>\n"
                            if $dbg_adv_checking;
			if (defined $cond) {
				substr($block, 0, length($cond), '');
			}
			if (statement_lines($cond) > 1) {
                            print "APW: ALLOWED: cond<$cond>\n"
                                if $dbg_adv_apw;
                            $allowed = 1;
			}
			if ($block =~/\b(?:if|for|while)\b/) {
                            print "APW: ALLOWED: block<$block>\n"
                                if $dbg_adv_apw;
                            $allowed = 1;
			}
			if (statement_block_size($block) > 1) {
                            print "APW: ALLOWED: lines block<$block>\n"
                                if $dbg_adv_apw;
                            $allowed = 1;
			}
			# Check the post-context.
			if (defined $chunks[1]) {
				my ($cond, $block) = @{$chunks[1]};
				if (defined $cond) {
					substr($block, 0, length($cond), '');
				}
				if ($block =~ /^\s*\{/) {
                                    print "APW: ALLOWED: chunk-1 block<$block>\n"
                                        if $dbg_adv_apw;
                                    $allowed = 1;
				}
			}
                        print "DCS: level=$level block<$block> allowed=$allowed\n"
                            if $dbg_adv_dcs;
			if ($level == 0 && $block !~ /^\s*\{/ && !$allowed) {
				my $herectx = $here . "\n";;
				my $cnt = statement_rawlines($block);

				for (my $n = 0; $n < $cnt; $n++) {
					$herectx .= raw_line($linenr, $n) . "\n";;
				}

				ERROR("braces {} are necessary even for single statement blocks\n" . $herectx);
			}
		}

# no volatiles please
		my $asm_volatile = qr{\b(__asm__|asm)\s+(__volatile__|volatile)\b};
		if ($line =~ /\bvolatile\b/ && $line !~ /$asm_volatile/ &&
                    $line !~ /sig_atomic_t/ &&
                    !ctx_has_comment($first_line, $linenr)) {
			my $msg = "Use of volatile is usually wrong, please add a comment\n" . $herecurr;
                        ERROR($msg);
		}

# warn about #if 0
		if ($line =~ /^.\s*\#\s*if\s+0\b/) {
			ERROR("if this code is redundant consider removing it\n" .
				$herecurr);
		}

# check for needless g_free() checks
		if ($prevline =~ /\bif\s*\(([^\)]*)\)/) {
			my $expr = $1;
			if ($line =~ /\bg_free\(\Q$expr\E\);/) {
				ERROR("g_free(NULL) is safe this check is probably not required\n" . $hereprev);
			}
		}

# warn about #ifdefs in C files
#		if ($line =~ /^.\s*\#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
#			print "#ifdef in C files should be avoided\n";
#			print "$herecurr";
#			$clean = 0;
#		}

# warn about spacing in #ifdefs
		if ($line =~ /^.\s*\#\s*(ifdef|ifndef|elif)\s\s+/) {
			ERROR("exactly one space required after that #$1\n" . $herecurr);
		}
# check for memory barriers without a comment.
		if ($line =~ /\b(smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
			if (!ctx_has_comment($first_line, $linenr)) {
				ERROR("memory barrier without comment\n" . $herecurr);
			}
		}
# check of hardware specific defines
# we have e.g. CONFIG_LINUX and CONFIG_WIN32 for common cases
# where they might be necessary.
		if ($line =~ m@^.\s*\#\s*if.*\b__@) {
			WARN("architecture specific defines should be avoided\n" .  $herecurr);
		}

# Check that the storage class is at the beginning of a declaration
		if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage\b/) {
			ERROR("storage class should be at the beginning of the declaration\n" . $herecurr)
		}

# check the location of the inline attribute, that it is between
# storage class and type.
		if ($line =~ /\b$Type\s+$Inline\b/ ||
		    $line =~ /\b$Inline\s+$Storage\b/) {
			ERROR("inline keyword should sit between storage class and type\n" . $herecurr);
		}

# check for sizeof(&)
		if ($line =~ /\bsizeof\s*\(\s*\&/) {
			ERROR("sizeof(& should be avoided\n" . $herecurr);
		}

# check for new externs in .c files.
		if ($realfile =~ /\.c$/ && defined $stat &&
		    $stat =~ /^.\s*(?:extern\s+)?$Type\s+($Ident)(\s*)\(/s)
		{
			my $function_name = $1;
			my $paren_space = $2;

			my $s = $stat;
			if (defined $cond) {
				substr($s, 0, length($cond), '');
			}
			if ($s =~ /^\s*;/ &&
			    $function_name ne 'uninitialized_var')
			{
				ERROR("externs should be avoided in .c files\n" .  $herecurr);
			}

			if ($paren_space =~ /\n/) {
				ERROR("arguments for function declarations should follow identifier\n" . $herecurr);
			}

		} elsif ($realfile =~ /\.c$/ && defined $stat &&
		    $stat =~ /^.\s*extern\s+/)
		{
			ERROR("externs should be avoided in .c files\n" .  $herecurr);
		}

# check for pointless casting of g_malloc return
		if ($line =~ /\*\s*\)\s*g_(try|)(m|re)alloc(0?)(_n)?\b/) {
			if ($2 eq 'm') {
				ERROR("unnecessary cast may hide bugs, use g_$1new$3 instead\n" . $herecurr);
			} else {
				ERROR("unnecessary cast may hide bugs, use g_$1renew$3 instead\n" . $herecurr);
			}
		}

# check for gcc specific __FUNCTION__
		if ($line =~ /__FUNCTION__/) {
			ERROR("__func__ should be used instead of gcc specific __FUNCTION__\n"  . $herecurr);
		}

# recommend g_path_get_* over g_strdup(basename/dirname(...))
		if ($line =~ /\bg_strdup\s*\(\s*(basename|dirname)\s*\(/) {
			WARN("consider using g_path_get_$1() in preference to g_strdup($1())\n" . $herecurr);
		}

# enforce g_memdup2() over g_memdup()
		if ($line =~ /\bg_memdup\s*\(/) {
			ERROR("use g_memdup2() instead of unsafe g_memdup()\n" . $herecurr);
		}

# recommend qemu_strto* over strto* for numeric conversions
		if ($line =~ /\b(strto[^kd].*?)\s*\(/) {
			ERROR("consider using qemu_$1 in preference to $1\n" . $herecurr);
		}
# recommend sigaction over signal for portability, when establishing a handler
		if ($line =~ /\bsignal\s*\(/ && !($line =~ /SIG_(?:IGN|DFL)/)) {
			ERROR("use sigaction to establish signal handlers; signal is not portable\n" . $herecurr);
		}
# recommend qemu_bh_new_guarded instead of qemu_bh_new
        if ($realfile =~ /.*\/hw\/.*/ && $line =~ /\bqemu_bh_new\s*\(/) {
			ERROR("use qemu_bh_new_guarded() instead of qemu_bh_new() to avoid reentrancy problems\n" . $herecurr);
		}
# recommend aio_bh_new_guarded instead of aio_bh_new
        if ($realfile =~ /.*\/hw\/.*/ && $line =~ /\baio_bh_new\s*\(/) {
			ERROR("use aio_bh_new_guarded() instead of aio_bh_new() to avoid reentrancy problems\n" . $herecurr);
		}
# check for module_init(), use category-specific init macros explicitly please
		if ($line =~ /^module_init\s*\(/) {
			ERROR("please use block_init(), type_init() etc. instead of module_init()\n" . $herecurr);
		}
# check for various ops structs, ensure they are const.
		my $struct_ops = qr{AIOCBInfo|
				BdrvActionOps|
				BlockDevOps|
				BlockJobDriver|
				DisplayChangeListenerOps|
				GraphicHwOps|
				IDEDMAOps|
				KVMCapabilityInfo|
				MemoryRegionIOMMUOps|
				MemoryRegionOps|
				MemoryRegionPortio|
				QEMUFileOps|
				SCSIBusInfo|
				SCSIReqOps|
				Spice[A-Z][a-zA-Z0-9]*Interface|
				TypeInfo|
				USBDesc[A-Z][a-zA-Z0-9]*|
				VhostOps|
				VMStateDescription|
				VMStateInfo}x;
		if ($line !~ /\bconst\b/ &&
		    $line =~ /\b($struct_ops)\b.*=/) {
			ERROR("initializer for struct $1 should normally be const\n" .
				$herecurr);
		}

# format strings checks
		my $string;
		while ($line =~ /(?:^|")([X\t]*)(?:"|$)/g) {
			$string = substr($rawline, $-[1], $+[1] - $-[1]);
			$string =~ s/%%/__/g;
			# check for %L{u,d,i} in strings
			if ($string =~ /(?<!%)%L[udi]/) {
				ERROR("\%Ld/%Lu are not-standard C, use %lld/%llu\n" . $herecurr);
			}
			# check for %# or %0# in printf-style format strings
			if ($string =~ /(?<!%)%0?#/) {
				ERROR("Don't use '#' flag of printf format " .
				      "('%#') in format strings, use '0x' " .
				      "prefix instead\n" . $herecurr);
			}
		}

# QEMU specific tests
		if ($rawline =~ /\b(?:Qemu|QEmu)\b/) {
			ERROR("use QEMU instead of Qemu or QEmu\n" . $herecurr);
		}

# Qemu error function tests

		# Find newlines in error messages
		my $qemu_error_funcs = qr{error_setg|
					 error_setg_errno|
					 error_setg_win32|
					 error_setg_file_open|
					 error_set|
					 error_prepend|
					 warn_reportf_err|
					 error_reportf_err|
					 error_vreport|
					 warn_vreport|
					 info_vreport|
					 error_report|
					 warn_report|
					 info_report|
					 g_test_message}x;

		if ($rawline =~ /\b(?:$qemu_error_funcs)\s*\(.*\".*\\n/) {
			ERROR("Error messages should not contain newlines\n" . $herecurr);
		}

		# Continue checking for error messages that contains newlines.
		# This check handles cases where string literals are spread
		# over multiple lines.
		# Example:
		# error_report("Error msg line #1"
		#              "Error msg line #2\n");
		my $quoted_newline_regex = qr{\+\s*\".*\\n.*\"};
		my $continued_str_literal = qr{\+\s*\".*\"};

		if ($rawline =~ /$quoted_newline_regex/) {
			# Backtrack to first line that does not contain only
			# a quoted literal and assume that it is the start
			# of the statement.
			my $i = $linenr - 2;

			while (($i >= 0) & $rawlines[$i] =~ /$continued_str_literal/) {
				$i--;
			}

			if ($rawlines[$i] =~ /\b(?:$qemu_error_funcs)\s*\(/) {
				ERROR("Error messages should not contain newlines\n" . $herecurr);
			}
		}

# check for non-portable libc calls that have portable alternatives in QEMU
		if ($line =~ /\bffs\(/) {
			ERROR("use ctz32() instead of ffs()\n" . $herecurr);
		}
		if ($line =~ /\bffsl\(/) {
			ERROR("use ctz32() or ctz64() instead of ffsl()\n" . $herecurr);
		}
		if ($line =~ /\bffsll\(/) {
			ERROR("use ctz64() instead of ffsll()\n" . $herecurr);
		}
		if ($line =~ /\bbzero\(/) {
			ERROR("use memset() instead of bzero()\n" . $herecurr);
		}
		if ($line =~ /\bgetpagesize\(\)/) {
			ERROR("use qemu_real_host_page_size() instead of getpagesize()\n" . $herecurr);
		}
		if ($line =~ /\bsysconf\(_SC_PAGESIZE\)/) {
			ERROR("use qemu_real_host_page_size() instead of sysconf(_SC_PAGESIZE)\n" . $herecurr);
		}
		if ($line =~ /\b(g_)?assert\(0\)/) {
			ERROR("use g_assert_not_reached() instead of assert(0)\n" . $herecurr);
		}
		if ($line =~ /\b(g_)?assert\(false\)/) {
			ERROR("use g_assert_not_reached() instead of assert(false)\n" .
			      $herecurr);
		}
		if ($line =~ /\bstrerrorname_np\(/) {
			ERROR("use strerror() instead of strerrorname_np()\n" . $herecurr);
		}
		my $non_exit_glib_asserts = qr{g_assert_cmpstr|
						g_assert_cmpint|
						g_assert_cmpuint|
						g_assert_cmphex|
						g_assert_cmpfloat|
						g_assert_true|
						g_assert_false|
						g_assert_nonnull|
						g_assert_null|
						g_assert_no_error|
						g_assert_error|
						g_test_assert_expected_messages|
						g_test_trap_assert_passed|
						g_test_trap_assert_stdout|
						g_test_trap_assert_stdout_unmatched|
						g_test_trap_assert_stderr|
						g_test_trap_assert_stderr_unmatched}x;
		if ($realfile !~ /^tests\// &&
			$line =~ /\b(?:$non_exit_glib_asserts)\(/) {
			ERROR("Use g_assert or g_assert_not_reached\n". $herecurr);
		}
	}

	if (defined $fileinfo) {
		process_end_of_file($fileinfo);
	}
	process_file_list(@fileinfolist);

	if ($is_patch && $chk_signoff && $signoff == 0) {
		ERROR("Missing Signed-off-by: line(s)\n");
	}

	# If we have no input at all, then there is nothing to report on
	# so just keep quiet.
	if ($#rawlines == -1) {
		return 1;
	}

	# In mailback mode only produce a report in the negative, for
	# things that appear to be patches.
	if ($mailback && ($clean == 1 || !$is_patch)) {
		return 1;
	}

	# This is not a patch, and we are are in 'no-patch' mode so
	# just keep quiet.
	if (!$chk_patch && !$is_patch) {
		return 1;
	}

	if (!$is_patch && $filename !~ /cover-letter\.patch$/) {
		ERROR("Does not appear to be a unified-diff format patch\n");
	}

	print report_dump();
	if ($summary && !($clean == 1 && $quiet == 1)) {
		print "$filename " if ($summary_file);
		print "total: $cnt_error errors, $cnt_warn warnings, " .
			"$cnt_lines lines checked\n";
		print "\n" if ($quiet == 0);
	}

	if ($quiet == 0) {
		# If there were whitespace errors which cleanpatch can fix
		# then suggest that.
#		if ($rpt_cleaners) {
#			print "NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or\n";
#			print "      scripts/cleanfile\n\n";
#		}
	}

	if ($clean == 1 && $quiet == 0) {
		print "$vname has no obvious style problems and is ready for submission.\n"
	}
	if ($clean == 0 && $quiet == 0) {
		print "$vname 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 ($no_warnings ? $clean : $cnt_error == 0);
}