#!/usr/bin/env perl
# SPDX-License-Identifier: GPL-2.0
#
# (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>
# (c) 2010-2018 Joe Perches <joe@perches.com>

use strict;
use warnings;
use POSIX;
use File::Basename;
use Cwd 'abs_path';
use Term::ANSIColor qw(:constants);

my $P = $0;
my $D = dirname(abs_path($P));

my $V = '0.32';

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

my $quiet = 0;
my $tree = 1;
my $chk_signoff = 1;
my $chk_patch = 1;
my $tst_only;
my $emacs = 0;
my $terse = 0;
my $showfile = 0;
my $file = 0;
my $git = 0;
my %git_commits = ();
my $check = 0;
my $check_orig = 0;
my $summary = 1;
my $mailback = 0;
my $summary_file = 0;
my $show_types = 0;
my $list_types = 0;
my $fix = 0;
my $fix_inplace = 0;
my $root;
my %debug;
my %camelcase = ();
my %use_type = ();
my @use = ();
my %ignore_type = ();
my @ignore = ();
my $help = 0;
my $configuration_file = ".checkpatch.conf";
my $max_line_length = 80;
my $ignore_perl_version = 0;
my $minimum_perl_version = 5.10.0;
my $min_conf_desc_length = 4;
my $spelling_file = "$D/spelling.txt";
my $codespell = 0;
my $codespellfile = "/usr/share/codespell/dictionary.txt";
my $conststructsfile = "$D/const_structs.checkpatch";
my $typedefsfile = "";
my $color = "auto";
my $allow_c99_comments = 1;

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

        print << "EOM";
Usage: $P [OPTION]... [FILE]...
Version: $V

Options:
  -q, --quiet                quiet
  --no-tree                  run without a kernel tree
  --no-signoff               do not check for 'Signed-off-by' line
  --patch                    treat FILE as patchfile (default)
  --emacs                    emacs compile window format
  --terse                    one line per report
  --showfile                 emit diffed file position, not input file position
  -g, --git                  treat FILE as a single commit or git revision range
                             single git commit with:
                               <rev>
                               <rev>^
                               <rev>~n
                             multiple git commits with:
                               <rev1>..<rev2>
                               <rev1>...<rev2>
                               <rev>-<count>
                             git merges are ignored
  -f, --file                 treat FILE as regular source file
  --subjective, --strict     enable more subjective tests
  --list-types               list the possible message types
  --types TYPE(,TYPE2...)    show only these comma separated message types
  --ignore TYPE(,TYPE2...)   ignore various comma separated message types
  --show-types               show the specific message type in the output
  --max-line-length=n        set the maximum line length, if exceeded, warn
  --min-conf-desc-length=n   set the min description length, if shorter, warn
  --root=PATH                PATH to the kernel 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
  --fix                      EXPERIMENTAL - may create horrible results
                             If correctable single-line errors exist, create
                             "<inputfile>.EXPERIMENTAL-checkpatch-fixes"
                             with potential errors corrected to the preferred
                             checkpatch style
  --fix-inplace              EXPERIMENTAL - may create horrible results
                             Is the same as --fix, but overwrites the input
                             file.  It's your fault if there's no backup or git
  --ignore-perl-version      override checking of perl version.  expect
                             runtime errors.
  --codespell                Use the codespell dictionary for spelling/typos
                             (default:/usr/share/codespell/dictionary.txt)
  --codespellfile            Use this codespell dictionary
  --typedefsfile             Read additional types from this file
  --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);
}

sub uniq {
        my %seen;
        return grep { !$seen{$_}++ } @_;
}

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

        my $count = 0;

        local $/ = undef;

        open(my $script, '<', abs_path($P)) or
            die "$P: Can't read '$P' $!\n";

        my $text = <$script>;
        close($script);

        my @types = ();
        # Also catch when type or level is passed through a variable
        for ($text =~ /(?:(?:\bCHK|\bWARN|\bERROR|&\{\$msg_level})\s*\(|\$msg_type\s*=)\s*"([^"]+)"/g) {
                push (@types, $_);
        }
        @types = sort(uniq(@types));
        print("#\tMessage type\n\n");
        foreach my $type (@types) {
                print(++$count . "\t" . $type . "\n");
        }

        exit($exitcode);
}

my $conf = which_conf($configuration_file);
if (-f $conf) {
        my @conf_args;
        open(my $conffile, '<', "$conf")
            or warn "$P: Can't find a readable $configuration_file file $!\n";

        while (<$conffile>) {
                my $line = $_;

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

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

                my @words = split(" ", $line);
                foreach my $word (@words) {
                        last if ($word =~ m/^#/);
                        push (@conf_args, $word);
                }
        }
        close($conffile);
        unshift(@ARGV, @conf_args) if @conf_args;
}

# 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,
        'emacs!'        => \$emacs,
        'terse!'        => \$terse,
        'showfile!'     => \$showfile,
        'f|file!'       => \$file,
        'g|git!'        => \$git,
        'subjective!'   => \$check,
        'strict!'       => \$check,
        'ignore=s'      => \@ignore,
        'types=s'       => \@use,
        'show-types!'   => \$show_types,
        'list-types!'   => \$list_types,
        'max-line-length=i' => \$max_line_length,
        'min-conf-desc-length=i' => \$min_conf_desc_length,
        'root=s'        => \$root,
        'summary!'      => \$summary,
        'mailback!'     => \$mailback,
        'summary-file!' => \$summary_file,
        'fix!'          => \$fix,
        'fix-inplace!'  => \$fix_inplace,
        'ignore-perl-version!' => \$ignore_perl_version,
        'debug=s'       => \%debug,
        'test-only=s'   => \$tst_only,
        'codespell!'    => \$codespell,
        'codespellfile=s'       => \$codespellfile,
        'typedefsfile=s'        => \$typedefsfile,
        'color=s'       => \$color,
        'no-color'      => \$color,     #keep old behaviors of -nocolor
        'nocolor'       => \$color,     #keep old behaviors of -nocolor
        'h|help'        => \$help,
        'version'       => \$help
) or help(1);

help(0) if ($help);

list_types(0) if ($list_types);

$fix = 1 if ($fix_inplace);
$check_orig = $check;

my $exit = 0;

if ($^V && $^V lt $minimum_perl_version) {
        printf "$P: requires at least perl version %vd\n", $minimum_perl_version;
        if (!$ignore_perl_version) {
                exit(1);
        }
}

#if no filenames are given, push '-' to read patch from stdin
if ($#ARGV < 0) {
        push(@ARGV, '-');
}

if ($color =~ /^[01]$/) {
        $color = !$color;
} elsif ($color =~ /^always$/i) {
        $color = 1;
} elsif ($color =~ /^never$/i) {
        $color = 0;
} elsif ($color =~ /^auto$/i) {
        $color = (-t STDOUT);
} else {
        die "Invalid color mode: $color\n";
}

sub hash_save_array_words {
        my ($hashRef, $arrayRef) = @_;

        my @array = split(/,/, join(',', @$arrayRef));
        foreach my $word (@array) {
                $word =~ s/\s*\n?$//g;
                $word =~ s/^\s*//g;
                $word =~ s/\s+/ /g;
                $word =~ tr/[a-z]/[A-Z]/;

                next if ($word =~ m/^\s*#/);
                next if ($word =~ m/^\s*$/);

                $hashRef->{$word}++;
        }
}

sub hash_show_words {
        my ($hashRef, $prefix) = @_;

        if (keys %$hashRef) {
                print "\nNOTE: $prefix message types:";
                foreach my $word (sort keys %$hashRef) {
                        print " $word";
                }
                print "\n";
        }
}

hash_save_array_words(\%ignore_type, \@ignore);
hash_save_array_words(\%use_type, \@use);

my $dbg_values = 0;
my $dbg_possible = 0;
my $dbg_type = 0;
my $dbg_attr = 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 kernel 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{
                        __user|
                        __kernel|
                        __force|
                        __iomem|
                        __must_check|
                        __init_refok|
                        __kprobes|
                        __ref|
                        __rcu|
                        __private
                }x;
our $InitAttributePrefix = qr{__(?:mem|cpu|dev|net_|)};
our $InitAttributeData = qr{$InitAttributePrefix(?:initdata\b)};
our $InitAttributeConst = qr{$InitAttributePrefix(?:initconst\b)};
our $InitAttributeInit = qr{$InitAttributePrefix(?:init\b)};
our $InitAttribute = qr{$InitAttributeData|$InitAttributeConst|$InitAttributeInit};

# Notes to $Attribute:
# We need \b after 'init' otherwise 'initconst' will cause a false positive in a check
our $Attribute  = qr{
                        const|
                        __percpu|
                        __nocast|
                        __safe|
                        __bitwise|
                        __packed__|
                        __packed2__|
                        __naked|
                        __maybe_unused|
                        __always_unused|
                        __noreturn|
                        __used|
                        __cold|
                        __pure|
                        __noclone|
                        __deprecated|
                        __read_mostly|
                        __kprobes|
                        $InitAttribute|
                        ____cacheline_aligned|
                        ____cacheline_aligned_in_smp|
                        ____cacheline_internodealigned_in_smp|
                        __weak
                  }x;
our $Modifier;
our $Inline     = qr{inline|__always_inline|noinline|__inline|__inline__};
our $Member     = qr{->$Ident|\.$Ident|\[[^]]*\]};
our $Lval       = qr{$Ident(?:$Member)*};

our $Int_type   = qr{(?i)llu|ull|ll|lu|ul|l|u};
our $Binary     = qr{(?i)0b[01]+$Int_type?};
our $Hex        = qr{(?i)0x[0-9a-f]+$Int_type?};
our $Int        = qr{[0-9]+$Int_type?};
our $Octal      = qr{0[0-7]+$Int_type?};
our $String     = qr{"[X\t]*"};
our $Float_hex  = qr{(?i)0x[0-9a-f]+p-?[0-9]+[fl]?};
our $Float_dec  = qr{(?i)(?:[0-9]+\.[0-9]*|[0-9]*\.[0-9]+)(?:e-?[0-9]+)?[fl]?};
our $Float_int  = qr{(?i)[0-9]+e-?[0-9]+[fl]?};
our $Float      = qr{$Float_hex|$Float_dec|$Float_int};
our $Constant   = qr{$Float|$Binary|$Octal|$Hex|$Int};
our $Assignment = qr{\*\=|/=|%=|\+=|-=|<<=|>>=|&=|\^=|\|=|=};
our $Compare    = qr{<=|>=|==|!=|<|(?<!-)>};
our $Arithmetic = qr{\+|-|\*|\/|%};
our $Operators  = qr{
                        <=|>=|==|!=|
                        =>|->|<<|>>|<|>|!|~|
                        &&|\|\||,|\^|\+\+|--|&|\||$Arithmetic
                  }x;

our $c90_Keywords = qr{do|for|while|if|else|return|goto|continue|switch|default|case|break}x;

our $BasicType;
our $NonptrType;
our $NonptrTypeMisordered;
our $NonptrTypeWithAttr;
our $Type;
our $TypeMisordered;
our $Declare;
our $DeclareMisordered;

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;

our $typeC99Typedefs = qr{(?:__)?(?:[us]_?)?int_?(?:8|16|32|64)_t};
our $typeOtherOSTypedefs = qr{(?x:
        u_(?:char|short|int|long) |          # bsd
        u(?:nchar|short|int|long)            # sysv
)};
our $typeKernelTypedefs = qr{(?x:
        (?:__)?(?:u|s|be|le)(?:8|16|32|64)|
        atomic_t
)};
our $typeTypedefs = qr{(?x:
        $typeC99Typedefs\b|
        $typeOtherOSTypedefs\b|
        $typeKernelTypedefs\b
)};

our $zero_initializer = qr{(?:(?:0[xX])?0+$Int_type?|NULL|false)\b};

our $logFunctions = qr{(?x:
        printk(?:_ratelimited|_once|_deferred_once|_deferred|)|
        (?:[a-z0-9]+_){1,2}(?:printk|emerg|alert|crit|err|warning|warn|notice|info|debug|dbg|vdbg|devel|cont|WARN)(?:_ratelimited|_once|)|
        TP_printk|
        WARN(?:_RATELIMIT|_ONCE|)|
        panic|
        MODULE_[A-Z_]+|
        seq_vprintf|seq_printf|seq_puts
)};

our $signature_tags = qr{(?xi:
        Signed-off-by:|
        Acked-by:|
        Tested-by:|
        Reviewed-by:|
        Reported-by:|
        Suggested-by:|
        To:|
        Cc:
)};

our @typeListMisordered = (
        qr{char\s+(?:un)?signed},
        qr{int\s+(?:(?:un)?signed\s+)?short\s},
        qr{int\s+short(?:\s+(?:un)?signed)},
        qr{short\s+int(?:\s+(?:un)?signed)},
        qr{(?:un)?signed\s+int\s+short},
        qr{short\s+(?:un)?signed},
        qr{long\s+int\s+(?:un)?signed},
        qr{int\s+long\s+(?:un)?signed},
        qr{long\s+(?:un)?signed\s+int},
        qr{int\s+(?:un)?signed\s+long},
        qr{int\s+(?:un)?signed},
        qr{int\s+long\s+long\s+(?:un)?signed},
        qr{long\s+long\s+int\s+(?:un)?signed},
        qr{long\s+long\s+(?:un)?signed\s+int},
        qr{long\s+long\s+(?:un)?signed},
        qr{long\s+(?:un)?signed},
);

our @typeList = (
        qr{void},
        qr{(?:(?:un)?signed\s+)?char},
        qr{(?:(?:un)?signed\s+)?short\s+int},
        qr{(?:(?:un)?signed\s+)?short},
        qr{(?:(?:un)?signed\s+)?int},
        qr{(?:(?:un)?signed\s+)?long\s+int},
        qr{(?:(?:un)?signed\s+)?long\s+long\s+int},
        qr{(?:(?:un)?signed\s+)?long\s+long},
        qr{(?:(?:un)?signed\s+)?long},
        qr{(?:un)?signed},
        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},
        @typeListMisordered,
);

our $C90_int_types = qr{(?x:
        long\s+long\s+int\s+(?:un)?signed|
        long\s+long\s+(?:un)?signed\s+int|
        long\s+long\s+(?:un)?signed|
        (?:(?:un)?signed\s+)?long\s+long\s+int|
        (?:(?:un)?signed\s+)?long\s+long|
        int\s+long\s+long\s+(?:un)?signed|
        int\s+(?:(?:un)?signed\s+)?long\s+long|

        long\s+int\s+(?:un)?signed|
        long\s+(?:un)?signed\s+int|
        long\s+(?:un)?signed|
        (?:(?:un)?signed\s+)?long\s+int|
        (?:(?:un)?signed\s+)?long|
        int\s+long\s+(?:un)?signed|
        int\s+(?:(?:un)?signed\s+)?long|

        int\s+(?:un)?signed|
        (?:(?:un)?signed\s+)?int
)};

our @typeListFile = ();
our @typeListWithAttr = (
        @typeList,
        qr{struct\s+$InitAttribute\s+$Ident},
        qr{union\s+$InitAttribute\s+$Ident},
);

our @modifierList = (
        qr{fastcall},
);
our @modifierListFile = ();

our @mode_permission_funcs = (
        ["module_param", 3],
        ["module_param_(?:array|named|string)", 4],
        ["module_param_array_named", 5],
        ["debugfs_create_(?:file|u8|u16|u32|u64|x8|x16|x32|x64|size_t|atomic_t|bool|blob|regset32|u32_array)", 2],
        ["proc_create(?:_data|)", 2],
        ["(?:CLASS|DEVICE|SENSOR|SENSOR_DEVICE|IIO_DEVICE)_ATTR", 2],
        ["IIO_DEV_ATTR_[A-Z_]+", 1],
        ["SENSOR_(?:DEVICE_|)ATTR_2", 2],
        ["SENSOR_TEMPLATE(?:_2|)", 3],
        ["__ATTR", 2],
);

#Create a search pattern for all these functions to speed up a loop below
our $mode_perms_search = "";
foreach my $entry (@mode_permission_funcs) {
        $mode_perms_search .= '|' if ($mode_perms_search ne "");
        $mode_perms_search .= $entry->[0];
}
$mode_perms_search = "(?:${mode_perms_search})";

our $mode_perms_world_writable = qr{
        S_IWUGO         |
        S_IWOTH         |
        S_IRWXUGO       |
        S_IALLUGO       |
        0[0-7][0-7][2367]
}x;

our %mode_permission_string_types = (
        "S_IRWXU" => 0700,
        "S_IRUSR" => 0400,
        "S_IWUSR" => 0200,
        "S_IXUSR" => 0100,
        "S_IRWXG" => 0070,
        "S_IRGRP" => 0040,
        "S_IWGRP" => 0020,
        "S_IXGRP" => 0010,
        "S_IRWXO" => 0007,
        "S_IROTH" => 0004,
        "S_IWOTH" => 0002,
        "S_IXOTH" => 0001,
        "S_IRWXUGO" => 0777,
        "S_IRUGO" => 0444,
        "S_IWUGO" => 0222,
        "S_IXUGO" => 0111,
);

#Create a search pattern for all these strings to speed up a loop below
our $mode_perms_string_search = "";
foreach my $entry (keys %mode_permission_string_types) {
        $mode_perms_string_search .= '|' if ($mode_perms_string_search ne "");
        $mode_perms_string_search .= $entry;
}
our $single_mode_perms_string_search = "(?:${mode_perms_string_search})";
our $multi_mode_perms_string_search = qr{
        ${single_mode_perms_string_search}
        (?:\s*\|\s*${single_mode_perms_string_search})*
}x;

sub perms_to_octal {
        my ($string) = @_;

        return trim($string) if ($string =~ /^\s*0[0-7]{3,3}\s*$/);

        my $val = "";
        my $oval = "";
        my $to = 0;
        my $curpos = 0;
        my $lastpos = 0;
        while ($string =~ /\b(($single_mode_perms_string_search)\b(?:\s*\|\s*)?\s*)/g) {
                $curpos = pos($string);
                my $match = $2;
                my $omatch = $1;
                last if ($lastpos > 0 && ($curpos - length($omatch) != $lastpos));
                $lastpos = $curpos;
                $to |= $mode_permission_string_types{$match};
                $val .= '\s*\|\s*' if ($val ne "");
                $val .= $match;
                $oval .= $omatch;
        }
        $oval =~ s/^\s*\|\s*//;
        $oval =~ s/\s*\|\s*$//;
        return sprintf("%04o", $to);
}

our $allowed_asm_includes = qr{(?x:
        irq|
        memory|
        time|
        reboot
)};
# memory.h: ARM has a custom one

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

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

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

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

                my ($suspect, $fix) = split(/\|\|/, $line);

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

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;

sub read_words {
        my ($wordsRef, $file) = @_;

        if (open(my $words, '<', $file)) {
                while (<$words>) {
                        my $line = $_;

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

                        next if ($line =~ m/^\s*#/);
                        next if ($line =~ m/^\s*$/);
                        if ($line =~ /\s/) {
                                print("$file: '$line' invalid - ignored\n");
                                next;
                        }

                        $$wordsRef .= '|' if ($$wordsRef ne "");
                        $$wordsRef .= $line;
                }
                close($file);
                return 1;
        }

        return 0;
}

my $const_structs = "";
read_words(\$const_structs, $conststructsfile)
    or warn "No structs that should be const will be found - file '$conststructsfile': $!\n";

my $typeOtherTypedefs = "";
if (length($typedefsfile)) {
        read_words(\$typeOtherTypedefs, $typedefsfile)
            or warn "No additional types will be considered - file '$typedefsfile': $!\n";
}
$typeTypedefs .= '|' . $typeOtherTypedefs if ($typeOtherTypedefs ne "");

sub build_types {
        my $mods = "(?x:  \n" . join("|\n  ", (@modifierList, @modifierListFile)) . "\n)";
        my $all = "(?x:  \n" . join("|\n  ", (@typeList, @typeListFile)) . "\n)";
        my $Misordered = "(?x:  \n" . join("|\n  ", @typeListMisordered) . "\n)";
        my $allWithAttr = "(?x:  \n" . join("|\n  ", @typeListWithAttr) . "\n)";
        $Modifier       = qr{(?:$Attribute|$Sparse|$mods)};
        $BasicType      = qr{
                                (?:$typeTypedefs\b)|
                                (?:${all}\b)
                }x;
        $NonptrType     = qr{
                        (?:$Modifier\s+|const\s+)*
                        (?:
                                (?:typeof|__typeof__)\s*\([^\)]*\)|
                                (?:$typeTypedefs\b)|
                                (?:${all}\b)
                        )
                        (?:\s+$Modifier|\s+const)*
                  }x;
        $NonptrTypeMisordered   = qr{
                        (?:$Modifier\s+|const\s+)*
                        (?:
                                (?:${Misordered}\b)
                        )
                        (?:\s+$Modifier|\s+const)*
                  }x;
        $NonptrTypeWithAttr     = qr{
                        (?:$Modifier\s+|const\s+)*
                        (?:
                                (?:typeof|__typeof__)\s*\([^\)]*\)|
                                (?:$typeTypedefs\b)|
                                (?:${allWithAttr}\b)
                        )
                        (?:\s+$Modifier|\s+const)*
                  }x;
        $Type   = qr{
                        $NonptrType
                        (?:(?:\s|\*|\[\])+\s*const|(?:\s|\*\s*(?:const\s*)?|\[\])+|(?:\s*\[\s*\])+)?
                        (?:\s+$Inline|\s+$Modifier)*
                  }x;
        $TypeMisordered = qr{
                        $NonptrTypeMisordered
                        (?:(?:\s|\*|\[\])+\s*const|(?:\s|\*\s*(?:const\s*)?|\[\])+|(?:\s*\[\s*\])+)?
                        (?:\s+$Inline|\s+$Modifier)*
                  }x;
        $Declare        = qr{(?:$Storage\s+(?:$Inline\s+)?)?$Type};
        $DeclareMisordered      = qr{(?:$Storage\s+(?:$Inline\s+)?)?$TypeMisordered};
}
build_types();

our $Typecast   = qr{\s*(\(\s*$NonptrType\s*\)){0,1}\s*};

# Using $balanced_parens, $LvalOrFunc, or $FuncArg
# requires at least perl version v5.10.0
# Any use must be runtime checked with $^V

our $balanced_parens = qr/(\((?:[^\(\)]++|(?-1))*\))/;
our $LvalOrFunc = qr{((?:[\&\*]\s*)?$Lval)\s*($balanced_parens{0,1})\s*};
our $FuncArg = qr{$Typecast{0,1}($LvalOrFunc|$Constant|$String)};

our $declaration_macros = qr{(?x:
        (?:$Storage\s+)?(?:[A-Z_][A-Z0-9]*_){0,2}(?:DEFINE|DECLARE)(?:_[A-Z0-9]+){1,6}\s*\(|
        (?:$Storage\s+)?[HLP]?LIST_HEAD\s*\(|
        (?:$Storage\s+)?${Type}\s+uninitialized_var\s*\(|
        (?:SKCIPHER_REQUEST|SHASH_DESC|AHASH_REQUEST)_ON_STACK\s*\(
)};

sub deparenthesize {
        my ($string) = @_;
        return "" if (!defined($string));

        while ($string =~ /^\s*\(.*\)\s*$/) {
                $string =~ s@^\s*\(\s*@@;
                $string =~ s@\s*\)\s*$@@;
        }

        $string =~ s@\s+@ @g;

        return $string;
}

sub seed_camelcase_file {
        my ($file) = @_;

        return if (!(-f $file));

        local $/;

        open(my $include_file, '<', "$file")
            or warn "$P: Can't read '$file' $!\n";
        my $text = <$include_file>;
        close($include_file);

        my @lines = split('\n', $text);

        foreach my $line (@lines) {
                next if ($line !~ /(?:[A-Z][a-z]|[a-z][A-Z])/);
                if ($line =~ /^[ \t]*(?:#[ \t]*define|typedef\s+$Type)\s+(\w*(?:[A-Z][a-z]|[a-z][A-Z])\w*)/) {
                        $camelcase{$1} = 1;
                } elsif ($line =~ /^\s*$Declare\s+(\w*(?:[A-Z][a-z]|[a-z][A-Z])\w*)\s*[\(\[,;]/) {
                        $camelcase{$1} = 1;
                } elsif ($line =~ /^\s*(?:union|struct|enum)\s+(\w*(?:[A-Z][a-z]|[a-z][A-Z])\w*)\s*[;\{]/) {
                        $camelcase{$1} = 1;
                }
        }
}

sub is_maintained_obsolete {
        my ($filename) = @_;

        return 0 if (!$tree || !(-e "$root/scripts/get_maintainer.pl"));

        my $status = `perl $root/scripts/get_maintainer.pl --status --nom --nol --nogit --nogit-fallback -f $filename 2>&1`;

        return $status =~ /obsolete/i;
}

my $camelcase_seeded = 0;
sub seed_camelcase_includes {
        return if ($camelcase_seeded);

        my $files;
        my $camelcase_cache = "";
        my @include_files = ();

        $camelcase_seeded = 1;

        if (-e ".git") {
                my $git_last_include_commit = `git log --no-merges --pretty=format:"%h%n" -1 -- include`;
                chomp $git_last_include_commit;
                $camelcase_cache = ".checkpatch-camelcase.git.$git_last_include_commit";
        } else {
                my $last_mod_date = 0;
                $files = `find $root/include -name "*.h"`;
                @include_files = split('\n', $files);
                foreach my $file (@include_files) {
                        my $date = POSIX::strftime("%Y%m%d%H%M",
                                                   localtime((stat $file)[9]));
                        $last_mod_date = $date if ($last_mod_date < $date);
                }
                $camelcase_cache = ".checkpatch-camelcase.date.$last_mod_date";
        }

        if ($camelcase_cache ne "" && -f $camelcase_cache) {
                open(my $camelcase_file, '<', "$camelcase_cache")
                    or warn "$P: Can't read '$camelcase_cache' $!\n";
                while (<$camelcase_file>) {
                        chomp;
                        $camelcase{$_} = 1;
                }
                close($camelcase_file);

                return;
        }

        if (-e ".git") {
                $files = `git ls-files "include/*.h"`;
                @include_files = split('\n', $files);
        }

        foreach my $file (@include_files) {
                seed_camelcase_file($file);
        }

        if ($camelcase_cache ne "") {
                unlink glob ".checkpatch-camelcase.*";
                open(my $camelcase_file, '>', "$camelcase_cache")
                    or warn "$P: Can't write '$camelcase_cache' $!\n";
                foreach (sort { lc($a) cmp lc($b) } keys(%camelcase)) {
                        print $camelcase_file ("$_\n");
                }
                close($camelcase_file);
        }
}

sub git_commit_info {
        my ($commit, $id, $desc) = @_;

        return ($id, $desc) if ((which("git") eq "") || !(-e ".git"));

        my $output = `git log --no-color --format='%H %s' -1 $commit 2>&1`;
        $output =~ s/^\s*//gm;
        my @lines = split("\n", $output);

        return ($id, $desc) if ($#lines < 0);

        if ($lines[0] =~ /^error: short SHA1 $commit is ambiguous\./) {
# Maybe one day convert this block of bash into something that returns
# all matching commit ids, but it's very slow...
#
#               echo "checking commits $1..."
#               git rev-list --remotes | grep -i "^$1" |
#               while read line ; do
#                   git log --format='%H %s' -1 $line |
#                   echo "commit $(cut -c 1-12,41-)"
#               done
        } elsif ($lines[0] =~ /^fatal: ambiguous argument '$commit': unknown revision or path not in the working tree\./) {
                $id = undef;
        } else {
                $id = substr($lines[0], 0, 12);
                $desc = substr($lines[0], 41);
        }

        return ($id, $desc);
}

$chk_signoff = 0 if ($file);

my @rawlines = ();
my @lines = ();
my @fixed = ();
my @fixed_inserted = ();
my @fixed_deleted = ();
my $fixlinenr = -1;

# If input is git commits, extract all commits from the commit expressions.
# For example, HEAD-3 means we need check 'HEAD, HEAD~1, HEAD~2'.
die "$P: No git repository found\n" if ($git && !-e ".git");

if ($git) {
        my @commits = ();
        foreach my $commit_expr (@ARGV) {
                my $git_range;
                if ($commit_expr =~ m/^(.*)-(\d+)$/) {
                        $git_range = "-$2 $1";
                } elsif ($commit_expr =~ m/\.\./) {
                        $git_range = "$commit_expr";
                } else {
                        $git_range = "-1 $commit_expr";
                }
                my $lines = `git log --no-color --no-merges --pretty=format:'%H %s' $git_range`;
                foreach my $line (split(/\n/, $lines)) {
                        $line =~ /^([0-9a-fA-F]{40,40}) (.*)$/;
                        next if (!defined($1) || !defined($2));
                        my $sha1 = $1;
                        my $subject = $2;
                        unshift(@commits, $sha1);
                        $git_commits{$sha1} = $subject;
                }
        }
        die "$P: no git commits after extraction!\n" if (@commits == 0);
        @ARGV = @commits;
}

my $vname;
for my $filename (@ARGV) {
        my $FILE;
        if ($git) {
                open($FILE, '-|', "git format-patch -M --stdout -1 $filename") ||
                        die "$P: $filename: git format-patch failed - $!\n";
        } elsif ($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 '-') {
                $vname = 'Your patch';
        } elsif ($git) {
                $vname = "Commit " . substr($filename, 0, 12) . ' ("' . $git_commits{$filename} . '")';
        } else {
                $vname = $filename;
        }
        while (<$FILE>) {
                chomp;

                push(@rawlines, $_);
        }
        close($FILE);

        if ($#ARGV > 0 && $quiet == 0) {
                print '-' x length($vname) . "\n";
                print "$vname\n";
                print '-' x length($vname) . "\n";
        }

        if (!process($filename)) {
                $exit = 1;
        }
        @rawlines = ();
        @lines = ();
        @fixed = ();
        @fixed_inserted = ();
        @fixed_deleted = ();
        $fixlinenr = -1;
        @modifierListFile = ();
        @typeListFile = ();
        build_types();
}

if (!$quiet) {
        hash_show_words(\%use_type, "Used");
        hash_show_words(\%ignore_type, "Ignored");

        if ($^V lt 5.10.0) {
                print << "EOM"

NOTE: perl $^V is not modern enough to detect all possible issues.
      An upgrade to at least perl v5.10.0 is suggested.
EOM
        }
        if ($exit) {
                print << "EOM"

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
EOM
        }
}

exit($exit);

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

        my @tree_check = (
                "COPYING", "CREDITS", "Kbuild", "MAINTAINERS", "Makefile",
                "README", "Documentation", "arch", "include", "drivers",
                "fs", "init", "ipc", "kernel", "lib", "scripts",
        );

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

sub parse_email {
        my ($formatted_email) = @_;

        my $name = "";
        my $address = "";
        my $comment = "";

        if ($formatted_email =~ /^(.*)<(\S+\@\S+)>(.*)$/) {
                $name = $1;
                $address = $2;
                $comment = $3 if defined $3;
        } elsif ($formatted_email =~ /^\s*<(\S+\@\S+)>(.*)$/) {
                $address = $1;
                $comment = $2 if defined $2;
        } elsif ($formatted_email =~ /(\S+\@\S+)(.*)$/) {
                $address = $1;
                $comment = $2 if defined $2;
                $formatted_email =~ s/\Q$address\E.*$//;
                $name = $formatted_email;
                $name = trim($name);
                $name =~ s/^\"|\"$//g;
                # If there's a name left after stripping spaces and
                # leading quotes, and the address doesn't have both
                # leading and trailing angle brackets, the address
                # is invalid. ie:
                #   "joe smith joe@smith.com" bad
                #   "joe smith <joe@smith.com" bad
                if ($name ne "" && $address !~ /^<[^>]+>$/) {
                        $name = "";
                        $address = "";
                        $comment = "";
                }
        }

        $name = trim($name);
        $name =~ s/^\"|\"$//g;
        $address = trim($address);
        $address =~ s/^\<|\>$//g;

        if ($name =~ /[^\w \-]/i) { ##has "must quote" chars
                $name =~ s/(?<!\\)"/\\"/g; ##escape quotes
                $name = "\"$name\"";
        }

        return ($name, $address, $comment);
}

sub format_email {
        my ($name, $address) = @_;

        my $formatted_email;

        $name = trim($name);
        $name =~ s/^\"|\"$//g;
        $address = trim($address);

        if ($name =~ /[^\w \-]/i) { ##has "must quote" chars
                $name =~ s/(?<!\\)"/\\"/g; ##escape quotes
                $name = "\"$name\"";
        }

        if ("$name" eq "") {
                $formatted_email = "$address";
        } else {
                $formatted_email = "$name <$address>";
        }

        return $formatted_email;
}

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

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

        return "";
}

sub which_conf {
        my ($conf) = @_;

        foreach my $path (split(/:/, ".:$ENV{HOME}:.scripts")) {
                if (-e "$path/$conf") {
                        return "$path/$conf";
                }
        }

        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 whacking 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@;
        }

        if ($allow_c99_comments && $res =~ m@(//.*$)@) {
                my $match = $1;
                $res =~ s/\Q$match\E/"$;" x length($match)/e;
        }

        return $res;
}

sub get_quoted_string {
        my ($line, $rawline) = @_;

        return "" if (!defined($line) || !defined($rawline));
        return "" if ($line !~ m/($String)/g);
        return substr($rawline, $-[0], $+[0] - $-[0]);
}

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 >= $len) {
                                last;
                        }
                        if ($level == 0 && substr($blk, $off) =~ /^.\s*#\s*define/) {
                                $level++;
                                $type = '#';
                        }
                }
                $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 ';') {
                                        $off++;
                                }
                                last;
                        }
                }
                # Preprocessor commands end at the newline unless escaped.
                if ($type eq '#' && $c eq "\n" && $p ne "\\") {
                        $level--;
                        $type = '';
                        $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 get_stat_real {
        my ($linenr, $lc) = @_;

        my $stat_real = raw_line($linenr, 0);
        for (my $count = $linenr + 1; $count <= $lc; $count++) {
                $stat_real = $stat_real . "\n" . raw_line($count, 0);
        }

        return $stat_real;
}

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

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

        return $herectx;
}

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(@modifierListFile, $modifier);
                                }
                        }

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

my $prefix = '';

sub show_type {
        my ($type) = @_;

        $type =~ tr/[a-z]/[A-Z]/;

        return defined $use_type{$type} if (scalar keys %use_type > 0);

        return !defined $ignore_type{$type};
}

sub report {
        my ($level, $type, $msg) = @_;

        if (!show_type($type) ||
            (defined $tst_only && $msg !~ /\Q$tst_only\E/)) {
                return 0;
        }
        my $output = '';
        if ($color) {
                if ($level eq 'ERROR') {
                        $output .= RED;
                } elsif ($level eq 'WARNING') {
                        $output .= YELLOW;
                } else {
                        $output .= GREEN;
                }
        }
        $output .= $prefix . $level . ':';
        if ($show_types) {
                $output .= BLUE if ($color);
                $output .= "$type:";
        }
        $output .= RESET if ($color);
        $output .= ' ' . $msg . "\n";

        if ($showfile) {
                my @lines = split("\n", $output, -1);
                splice(@lines, 1, 1);
                $output = join("\n", @lines);
        }
        $output = (split('\n', $output))[0] . "\n" if ($terse);

        push(our @report, $output);

        return 1;
}

sub report_dump {
        our @report;
}

sub fixup_current_range {
        my ($lineRef, $offset, $length) = @_;

        if ($$lineRef =~ /^\@\@ -\d+,\d+ \+(\d+),(\d+) \@\@/) {
                my $o = $1;
                my $l = $2;
                my $no = $o + $offset;
                my $nl = $l + $length;
                $$lineRef =~ s/\+$o,$l \@\@/\+$no,$nl \@\@/;
        }
}

sub fix_inserted_deleted_lines {
        my ($linesRef, $insertedRef, $deletedRef) = @_;

        my $range_last_linenr = 0;
        my $delta_offset = 0;

        my $old_linenr = 0;
        my $new_linenr = 0;

        my $next_insert = 0;
        my $next_delete = 0;

        my @lines = ();

        my $inserted = @{$insertedRef}[$next_insert++];
        my $deleted = @{$deletedRef}[$next_delete++];

        foreach my $old_line (@{$linesRef}) {
                my $save_line = 1;
                my $line = $old_line;   #don't modify the array
                if ($line =~ /^(?:\+\+\+|\-\-\-)\s+\S+/) {      #new filename
                        $delta_offset = 0;
                } elsif ($line =~ /^\@\@ -\d+,\d+ \+\d+,\d+ \@\@/) {    #new hunk
                        $range_last_linenr = $new_linenr;
                        fixup_current_range(\$line, $delta_offset, 0);
                }

                while (defined($deleted) && ${$deleted}{'LINENR'} == $old_linenr) {
                        $deleted = @{$deletedRef}[$next_delete++];
                        $save_line = 0;
                        fixup_current_range(\$lines[$range_last_linenr], $delta_offset--, -1);
                }

                while (defined($inserted) && ${$inserted}{'LINENR'} == $old_linenr) {
                        push(@lines, ${$inserted}{'LINE'});
                        $inserted = @{$insertedRef}[$next_insert++];
                        $new_linenr++;
                        fixup_current_range(\$lines[$range_last_linenr], $delta_offset++, 1);
                }

                if ($save_line) {
                        push(@lines, $line);
                        $new_linenr++;
                }

                $old_linenr++;
        }

        return @lines;
}

sub fix_insert_line {
        my ($linenr, $line) = @_;

        my $inserted = {
                LINENR => $linenr,
                LINE => $line,
        };
        push(@fixed_inserted, $inserted);
}

sub fix_delete_line {
        my ($linenr, $line) = @_;

        my $deleted = {
                LINENR => $linenr,
                LINE => $line,
        };

        push(@fixed_deleted, $deleted);
}

sub ERROR {
        my ($type, $msg) = @_;

        if (report("ERROR", $type, $msg)) {
                our $clean = 0;
                our $cnt_error++;
                return 1;
        }
        return 0;
}
sub WARN {
        my ($type, $msg) = @_;

        if (report("WARNING", $type, $msg)) {
                our $clean = 0;
                our $cnt_warn++;
                return 1;
        }
        return 0;
}
sub CHK {
        my ($type, $msg) = @_;

        if ($check && report("CHECK", $type, $msg)) {
                our $clean = 0;
                our $cnt_chk++;
                return 1;
        }
        return 0;
}

sub check_absolute_file {
        my ($absolute, $herecurr) = @_;
        my $file = $absolute;

        ##print "absolute<$absolute>\n";

        # See if any suffix of this path is a path within the tree.
        while ($file =~ s@^[^/]*/@@) {
                if (-f "$root/$file") {
                        ##print "file<$file>\n";
                        last;
                }
        }
        if (! -f _)  {
                return 0;
        }

        # It is, so see if the prefix is acceptable.
        my $prefix = $absolute;
        substr($prefix, -length($file)) = '';

        ##print "prefix<$prefix>\n";
        if ($prefix ne ".../") {
                WARN("USE_RELATIVE_PATH",
                     "use relative pathname instead of absolute in changelog text\n" . $herecurr);
        }
}

sub trim {
        my ($string) = @_;

        $string =~ s/^\s+|\s+$//g;

        return $string;
}

sub ltrim {
        my ($string) = @_;

        $string =~ s/^\s+//;

        return $string;
}

sub rtrim {
        my ($string) = @_;

        $string =~ s/\s+$//;

        return $string;
}

sub string_find_replace {
        my ($string, $find, $replace) = @_;

        $string =~ s/$find/$replace/g;

        return $string;
}

sub tabify {
        my ($leading) = @_;

        my $source_indent = 8;
        my $max_spaces_before_tab = $source_indent - 1;
        my $spaces_to_tab = " " x $source_indent;

        #convert leading spaces to tabs
        1 while $leading =~ s@^([\t]*)$spaces_to_tab@$1\t@g;
        #Remove spaces before a tab
        1 while $leading =~ s@^([\t]*)( {1,$max_spaces_before_tab})\t@$1\t@g;

        return "$leading";
}

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

        my $pos = 0;

        my $opens = $line =~ tr/\(/\(/;
        my $closes = $line =~ tr/\)/\)/;

        my $last_openparen = 0;

        if (($opens == 0) || ($closes >= $opens)) {
                return -1;
        }

        my $len = length($line);

        for ($pos = 0; $pos < $len; $pos++) {
                my $string = substr($line, $pos);
                if ($string =~ /^($FuncArg|$balanced_parens)/) {
                        $pos += length($1) - 1;
                } elsif (substr($line, $pos, 1) eq '(') {
                        $last_openparen = $pos;
                } elsif (index($string, '(') == -1) {
                        last;
                }
        }

        return length(expand_tabs(substr($line, 0, $last_openparen))) + 1;
}

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 $has_commit_log = 0;         #Encountered lines before patch
        my $commit_log_possible_stack_dump = 0;
        my $commit_log_long_line = 0;
        my $commit_log_has_diff = 0;
        my $reported_maintainer_file = 0;
        my $non_utf8_charset = 0;

        my $last_blank_line = 0;
        my $last_coalesced_string_linenr = -1;

        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 $here = '';
        my $context_function;           #undef'd unless there's a known function
        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;
        my $suppress_statement = 0;

        my %signatures = ();

        # Pre-scan the patch sanitizing the lines.
        # Pre-scan the patch looking for any __setup documentation.
        #
        my @setup_docs = ();
        my $setup_docs = 0;

        my $camelcase_file_seeded = 0;

        my $checklicenseline = 1;

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

                push(@fixed, $rawline) if ($fix);

                if ($rawline=~/^\+\+\+\s+(\S+)/) {
                        $setup_docs = 0;
                        if ($1 =~ m@Documentation/admin-guide/kernel-parameters.rst$@) {
                                $setup_docs = 1;
                        }
                        #next;
                }
                if ($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";

                if ($setup_docs && $line =~ /^\+/) {
                        push(@setup_docs, $line);
                }
        }

        $prefix = '';

        $realcnt = 0;
        $linenr = 0;
        $fixlinenr = -1;
        foreach my $line (@lines) {
                $linenr++;
                $fixlinenr++;
                my $sline = $line;      #copy of $line
                $sline =~ s/$;/ /g;     #with comments as spaces

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

# check if it's a mode change, rename or start of a patch
                if (!$in_commit_log &&
                    ($line =~ /^ mode change [0-7]+ => [0-7]+ \S+\s*$/ ||
                    ($line =~ /^rename (?:from|to) \S+\s*$/ ||
                     $line =~ /^diff --git a\/[\w\/\.\_\-]+ b\/\S+\s*$/))) {
                        $is_patch = 1;
                }

#extract the line range in the file after the patch is applied
                if (!$in_commit_log &&
                    $line =~ /^\@\@ -\d+(?:,\d+)? \+(\d+)(,(\d+))? \@\@(.*)/) {
                        my $context = $4;
                        $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 = ();
                        $suppress_statement = 0;
                        if ($context =~ /\b(\w+)\s*\(/) {
                                $context_function = $1;
                        } else {
                                undef $context_function;
                        }
                        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);

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

                my $found_file = 0;
                # extract the filename as it passes
                if ($line =~ /^diff --git.*?(\S+)$/) {
                        $realfile = $1;
                        $realfile =~ s@^([^/]*)/@@ if (!$file);
                        $in_commit_log = 0;
                        $found_file = 1;
                } elsif ($line =~ /^\+\+\+\s+(\S+)/) {
                        $realfile = $1;
                        $realfile =~ s@^([^/]*)/@@ if (!$file);
                        $in_commit_log = 0;

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

                        if ($realfile =~ m@^include/asm/@) {
                                ERROR("MODIFIED_INCLUDE_ASM",
                                      "do not modify files in include/asm, change architecture specific files in include/asm-<architecture>\n" . "$here$rawline\n");
                        }
                        $found_file = 1;
                }

#make up the handle for any error we report on this line
                if ($showfile) {
                        $prefix = "$realfile:$realline: "
                } elsif ($emacs) {
                        if ($file) {
                                $prefix = "$filename:$realline: ";
                        } else {
                                $prefix = "$filename:$linenr: ";
                        }
                }

                if ($found_file) {
                        if (is_maintained_obsolete($realfile)) {
                                WARN("OBSOLETE",
                                     "$realfile is marked as 'obsolete' in the MAINTAINERS hierarchy.  No unnecessary modifications please.\n");
                        }
                        if ($realfile =~ m@^(?:drivers/net/|net/|drivers/staging/)@) {
                                $check = 1;
                        } else {
                                $check = $check_orig;
                        }
                        $checklicenseline = 1;
                        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);

# Check if the commit log has what seems like a diff which can confuse patch
                if ($in_commit_log && !$commit_log_has_diff &&
                    (($line =~ m@^\s+diff\b.*a/[\w/]+@ &&
                      $line =~ m@^\s+diff\b.*a/([\w/]+)\s+b/$1\b@) ||
                     $line =~ m@^\s*(?:\-\-\-\s+a/|\+\+\+\s+b/)@ ||
                     $line =~ m/^\s*\@\@ \-\d+,\d+ \+\d+,\d+ \@\@/)) {
                        ERROR("DIFF_IN_COMMIT_MSG",
                              "Avoid using diff content in the commit message - patch(1) might not work\n" . $herecurr);
                        $commit_log_has_diff = 1;
                }

# Check for incorrect file permissions
                if ($line =~ /^new (file )?mode.*[7531]\d{0,2}$/) {
                        my $permhere = $here . "FILE: $realfile\n";
                        if ($realfile !~ m@scripts/@ &&
                            $realfile !~ /\.(py|pl|awk|sh)$/) {
                                ERROR("EXECUTE_PERMISSIONS",
                                      "do not set execute permissions for source files\n" . $permhere);
                        }
                }

# Check the patch for a signoff:
                if ($line =~ /^\s*signed-off-by:/i) {
                        $signoff++;
                        $in_commit_log = 0;
                }

# Check if MAINTAINERS is being updated.  If so, there's probably no need to
# emit the "does MAINTAINERS need updating?" message on file add/move/delete
                if ($line =~ /^\s*MAINTAINERS\s*\|/) {
                        $reported_maintainer_file = 1;
                }

# Check signature styles
                if (!$in_header_lines &&
                    $line =~ /^(\s*)([a-z0-9_-]+by:|$signature_tags)(\s*)(.*)/i) {
                        my $space_before = $1;
                        my $sign_off = $2;
                        my $space_after = $3;
                        my $email = $4;
                        my $ucfirst_sign_off = ucfirst(lc($sign_off));

                        if ($sign_off !~ /$signature_tags/) {
                                WARN("BAD_SIGN_OFF",
                                     "Non-standard signature: $sign_off\n" . $herecurr);
                        }
                        if (defined $space_before && $space_before ne "") {
                                if (WARN("BAD_SIGN_OFF",
                                         "Do not use whitespace before $ucfirst_sign_off\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =
                                            "$ucfirst_sign_off $email";
                                }
                        }
                        if ($sign_off =~ /-by:$/i && $sign_off ne $ucfirst_sign_off) {
                                if (WARN("BAD_SIGN_OFF",
                                         "'$ucfirst_sign_off' is the preferred signature form\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =
                                            "$ucfirst_sign_off $email";
                                }

                        }
                        if (!defined $space_after || $space_after ne " ") {
                                if (WARN("BAD_SIGN_OFF",
                                         "Use a single space after $ucfirst_sign_off\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =
                                            "$ucfirst_sign_off $email";
                                }
                        }

                        my ($email_name, $email_address, $comment) = parse_email($email);
                        my $suggested_email = format_email(($email_name, $email_address));
                        if ($suggested_email eq "") {
                                ERROR("BAD_SIGN_OFF",
                                      "Unrecognized email address: '$email'\n" . $herecurr);
                        } else {
                                my $dequoted = $suggested_email;
                                $dequoted =~ s/^"//;
                                $dequoted =~ s/" </ </;
                                # Don't force email to have quotes
                                # Allow just an angle bracketed address
                                if ("$dequoted$comment" ne $email &&
                                    "<$email_address>$comment" ne $email &&
                                    "$suggested_email$comment" ne $email) {
                                        WARN("BAD_SIGN_OFF",
                                             "email address '$email' might be better as '$suggested_email$comment'\n" . $herecurr);
                                }
                        }

# Check for duplicate signatures
                        my $sig_nospace = $line;
                        $sig_nospace =~ s/\s//g;
                        $sig_nospace = lc($sig_nospace);
                        if (defined $signatures{$sig_nospace}) {
                                WARN("BAD_SIGN_OFF",
                                     "Duplicate signature\n" . $herecurr);
                        } else {
                                $signatures{$sig_nospace} = 1;
                        }
                }

# Check email subject for common tools that don't need to be mentioned
                if ($in_header_lines &&
                    $line =~ /^Subject:.*\b(?:checkpatch|sparse|smatch)\b[^:]/i) {
                        WARN("EMAIL_SUBJECT",
                             "A patch subject line should describe the change not the tool that found it\n" . $herecurr);
                }

# Check for unwanted Gerrit info
                if ($in_commit_log && $line =~ /^\s*change-id:/i) {
                        ERROR("GERRIT_CHANGE_ID",
                              "Remove Gerrit Change-Id's before submitting upstream.\n" . $herecurr);
                }

# Check if the commit log is in a possible stack dump
                if ($in_commit_log && !$commit_log_possible_stack_dump &&
                    ($line =~ /^\s*(?:WARNING:|BUG:)/ ||
                     $line =~ /^\s*\[\s*\d+\.\d{6,6}\s*\]/ ||
                                        # timestamp
                     $line =~ /^\s*\[\<[0-9a-fA-F]{8,}\>\]/)) {
                                        # stack dump address
                        $commit_log_possible_stack_dump = 1;
                }

# Check for line lengths > 75 in commit log, warn once
                if ($in_commit_log && !$commit_log_long_line &&
                    length($line) > 75 &&
                    !($line =~ /^\s*[a-zA-Z0-9_\/\.]+\s+\|\s+\d+/ ||
                                        # file delta changes
                      $line =~ /^\s*(?:[\w\.\-]+\/)++[\w\.\-]+:/ ||
                                        # filename then :
                      $line =~ /^\s*(?:Fixes:|Link:)/i ||
                                        # A Fixes: or Link: line
                      $commit_log_possible_stack_dump)) {
                        WARN("COMMIT_LOG_LONG_LINE",
                             "Possible unwrapped commit description (prefer a maximum 75 chars per line)\n" . $herecurr);
                        $commit_log_long_line = 1;
                }

# Reset possible stack dump if a blank line is found
                if ($in_commit_log && $commit_log_possible_stack_dump &&
                    $line =~ /^\s*$/) {
                        $commit_log_possible_stack_dump = 0;
                }

# Check for git id commit length and improperly formed commit descriptions
                if ($in_commit_log && !$commit_log_possible_stack_dump &&
                    $line !~ /^\s*(?:Link|Patchwork|http|https|BugLink):/i &&
                    $line !~ /^This reverts commit [0-9a-f]{7,40}/ &&
                    ($line =~ /\bcommit\s+[0-9a-f]{5,}\b/i ||
                     ($line =~ /(?:\s|^)[0-9a-f]{12,40}(?:[\s"'\(\[]|$)/i &&
                      $line !~ /[\<\[][0-9a-f]{12,40}[\>\]]/i &&
                      $line !~ /\bfixes:\s*[0-9a-f]{12,40}/i))) {
                        my $init_char = "c";
                        my $orig_commit = "";
                        my $short = 1;
                        my $long = 0;
                        my $case = 1;
                        my $space = 1;
                        my $hasdesc = 0;
                        my $hasparens = 0;
                        my $id = '0123456789ab';
                        my $orig_desc = "commit description";
                        my $description = "";

                        if ($line =~ /\b(c)ommit\s+([0-9a-f]{5,})\b/i) {
                                $init_char = $1;
                                $orig_commit = lc($2);
                        } elsif ($line =~ /\b([0-9a-f]{12,40})\b/i) {
                                $orig_commit = lc($1);
                        }

                        $short = 0 if ($line =~ /\bcommit\s+[0-9a-f]{12,40}/i);
                        $long = 1 if ($line =~ /\bcommit\s+[0-9a-f]{41,}/i);
                        $space = 0 if ($line =~ /\bcommit [0-9a-f]/i);
                        $case = 0 if ($line =~ /\b[Cc]ommit\s+[0-9a-f]{5,40}[^A-F]/);
                        if ($line =~ /\bcommit\s+[0-9a-f]{5,}\s+\("([^"]+)"\)/i) {
                                $orig_desc = $1;
                                $hasparens = 1;
                        } elsif ($line =~ /\bcommit\s+[0-9a-f]{5,}\s*$/i &&
                                 defined $rawlines[$linenr] &&
                                 $rawlines[$linenr] =~ /^\s*\("([^"]+)"\)/) {
                                $orig_desc = $1;
                                $hasparens = 1;
                        } elsif ($line =~ /\bcommit\s+[0-9a-f]{5,}\s+\("[^"]+$/i &&
                                 defined $rawlines[$linenr] &&
                                 $rawlines[$linenr] =~ /^\s*[^"]+"\)/) {
                                $line =~ /\bcommit\s+[0-9a-f]{5,}\s+\("([^"]+)$/i;
                                $orig_desc = $1;
                                $rawlines[$linenr] =~ /^\s*([^"]+)"\)/;
                                $orig_desc .= " " . $1;
                                $hasparens = 1;
                        }

                        ($id, $description) = git_commit_info($orig_commit,
                                                              $id, $orig_desc);

                        if (defined($id) &&
                           ($short || $long || $space || $case || ($orig_desc ne $description) || !$hasparens)) {
                                ERROR("GIT_COMMIT_ID",
                                      "Please use git commit description style 'commit <12+ chars of sha1> (\"<title line>\")' - ie: '${init_char}ommit $id (\"$description\")'\n" . $herecurr);
                        }
                }

# Check for added, moved or deleted files
                if (!$reported_maintainer_file && !$in_commit_log &&
                    ($line =~ /^(?:new|deleted) file mode\s*\d+\s*$/ ||
                     $line =~ /^rename (?:from|to) [\w\/\.\-]+\s*$/ ||
                     ($line =~ /\{\s*([\w\/\.\-]*)\s*\=\>\s*([\w\/\.\-]*)\s*\}/ &&
                      (defined($1) || defined($2))))) {
                        $is_patch = 1;
                        $reported_maintainer_file = 1;
                        WARN("FILE_PATH_CHANGES",
                             "added, moved or deleted file(s), does MAINTAINERS need updating?\n" . $herecurr);
                }

# Check for wrappage within a valid hunk of the file
                if ($realcnt != 0 && $line !~ m{^(?:\+|-| |\\ No newline|$)}) {
                        ERROR("CORRUPTED_PATCH",
                              "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";

                        CHK("INVALID_UTF8",
                            "Invalid UTF-8, patch and commit message should be encoded in UTF-8\n" . $hereptr);
                }

# 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;
                        $has_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("UTF8_BEFORE_PATCH",
                            "8-bit UTF-8 used in possible commit log\n" . $herecurr);
                }

# Check for absolute kernel paths in commit message
                if ($tree && $in_commit_log) {
                        while ($line =~ m{(?:^|\s)(/\S*)}g) {
                                my $file = $1;

                                if ($file =~ m{^(.*?)(?::\d+)+:?$} &&
                                    check_absolute_file($1, $herecurr)) {
                                        #
                                } else {
                                        check_absolute_file($file, $herecurr);
                                }
                        }
                }

# Check for various typo / spelling mistakes
                if (defined($misspellings) &&
                    ($in_commit_log || $line =~ /^(?:\+|Subject:)/i)) {
                        while ($rawline =~ /(?:^|[^a-z@])($misspellings)(?:\b|$|[^a-z@])/gi) {
                                my $typo = $1;
                                my $typo_fix = $spelling_fix{lc($typo)};
                                $typo_fix = ucfirst($typo_fix) if ($typo =~ /^[A-Z]/);
                                $typo_fix = uc($typo_fix) if ($typo =~ /^[A-Z]+$/);
                                my $msg_level = \&WARN;
                                $msg_level = \&CHK if ($file);
                                if (&{$msg_level}("TYPO_SPELLING",
                                                  "'$typo' may be misspelled - perhaps '$typo_fix'?\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/(^|[^A-Za-z@])($typo)($|[^A-Za-z@])/$1$typo_fix$3/;
                                }
                        }
                }

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

#trailing whitespace
                if ($line =~ /^\+.*\015/) {
                        my $herevet = "$here\n" . cat_vet($rawline) . "\n";
                        if (ERROR("DOS_LINE_ENDINGS",
                                  "DOS line endings\n" . $herevet) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/[\s\015]+$//;
                        }
                } elsif ($rawline =~ /^\+.*\S\s+$/ || $rawline =~ /^\+\s+$/) {
                        my $herevet = "$here\n" . cat_vet($rawline) . "\n";
                        if (ERROR("TRAILING_WHITESPACE",
                                  "trailing whitespace\n" . $herevet) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\s+$//;
                        }

                        $rpt_cleaners = 1;
                }

# Check for FSF mailing addresses.
                if ($rawline =~ /\bwrite to the Free/i ||
                    $rawline =~ /\b675\s+Mass\s+Ave/i ||
                    $rawline =~ /\b59\s+Temple\s+Pl/i ||
                    $rawline =~ /\b51\s+Franklin\s+St/i) {
                        my $herevet = "$here\n" . cat_vet($rawline) . "\n";
                        my $msg_level = \&ERROR;
                        $msg_level = \&CHK if ($file);
                        &{$msg_level}("FSF_MAILING_ADDRESS",
                                      "Do not include the paragraph about writing to the Free Software Foundation's mailing address from the sample GPL notice. The FSF has changed addresses in the past, and may do so again. Linux already includes a copy of the GPL.\n" . $herevet)
                }

# check for Kconfig help text having a real description
# Only applies when adding the entry originally, after that we do not have
# sufficient context to determine whether it is indeed long enough.
                if ($realfile =~ /Kconfig/ &&
                    # 'choice' is usually the last thing on the line (though
                    # Kconfig supports named choices), so use a word boundary
                    # (\b) rather than a whitespace character (\s)
                    $line =~ /^\+\s*(?:config|menuconfig|choice)\b/) {
                        my $length = 0;
                        my $cnt = $realcnt;
                        my $ln = $linenr + 1;
                        my $f;
                        my $is_start = 0;
                        my $is_end = 0;
                        for (; $cnt > 0 && defined $lines[$ln - 1]; $ln++) {
                                $f = $lines[$ln - 1];
                                $cnt-- if ($lines[$ln - 1] !~ /^-/);
                                $is_end = $lines[$ln - 1] =~ /^\+/;

                                next if ($f =~ /^-/);
                                last if (!$file && $f =~ /^\@\@/);

                                if ($lines[$ln - 1] =~ /^\+\s*(?:bool|tristate|prompt)\s*["']/) {
                                        $is_start = 1;
                                } elsif ($lines[$ln - 1] =~ /^\+\s*(?:help|---help---)\s*$/) {
                                        if ($lines[$ln - 1] =~ "---help---") {
                                                WARN("CONFIG_DESCRIPTION",
                                                     "prefer 'help' over '---help---' for new help texts\n" . $herecurr);
                                        }
                                        $length = -1;
                                }

                                $f =~ s/^.//;
                                $f =~ s/#.*//;
                                $f =~ s/^\s+//;
                                next if ($f =~ /^$/);

                                # This only checks context lines in the patch
                                # and so hopefully shouldn't trigger false
                                # positives, even though some of these are
                                # common words in help texts
                                if ($f =~ /^\s*(?:config|menuconfig|choice|endchoice|
                                                  if|endif|menu|endmenu|source)\b/x) {
                                        $is_end = 1;
                                        last;
                                }
                                $length++;
                        }
                        if ($is_start && $is_end && $length < $min_conf_desc_length) {
                                WARN("CONFIG_DESCRIPTION",
                                     "please write a paragraph that describes the config symbol fully\n" . $herecurr);
                        }
                        #print "is_start<$is_start> is_end<$is_end> length<$length>\n";
                }

# check for MAINTAINERS entries that don't have the right form
                if ($realfile =~ /^MAINTAINERS$/ &&
                    $rawline =~ /^\+[A-Z]:/ &&
                    $rawline !~ /^\+[A-Z]:\t\S/) {
                        if (WARN("MAINTAINERS_STYLE",
                                 "MAINTAINERS entries use one tab after TYPE:\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/^(\+[A-Z]):\s*/$1:\t/;
                        }
                }

# discourage the use of boolean for type definition attributes of Kconfig options
                if ($realfile =~ /Kconfig/ &&
                    $line =~ /^\+\s*\bboolean\b/) {
                        WARN("CONFIG_TYPE_BOOLEAN",
                             "Use of boolean is deprecated, please use bool instead.\n" . $herecurr);
                }

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

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

# check for DT compatible documentation
                if (defined $root &&
                        (($realfile =~ /\.dtsi?$/ && $line =~ /^\+\s*compatible\s*=\s*\"/) ||
                         ($realfile =~ /\.[ch]$/ && $line =~ /^\+.*\.compatible\s*=\s*\"/))) {

                        my @compats = $rawline =~ /\"([a-zA-Z0-9\-\,\.\+_]+)\"/g;

                        my $dt_path = $root . "/Documentation/devicetree/bindings/";
                        my $vp_file = $dt_path . "vendor-prefixes.txt";

                        foreach my $compat (@compats) {
                                my $compat2 = $compat;
                                $compat2 =~ s/\,[a-zA-Z0-9]*\-/\,<\.\*>\-/;
                                my $compat3 = $compat;
                                $compat3 =~ s/\,([a-z]*)[0-9]*\-/\,$1<\.\*>\-/;
                                `grep -Erq "$compat|$compat2|$compat3" $dt_path`;
                                if ( $? >> 8 ) {
                                        WARN("UNDOCUMENTED_DT_STRING",
                                             "DT compatible string \"$compat\" appears un-documented -- check $dt_path\n" . $herecurr);
                                }

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

# check for using SPDX license tag at beginning of files
                if ($realline == $checklicenseline) {
                        if ($rawline =~ /^[ \+]\s*\#\!\s*\//) {
                                $checklicenseline = 2;
                        } elsif ($rawline =~ /^\+/) {
                                my $comment = "";
                                if ($realfile =~ /\.(h|s|S)$/) {
                                        $comment = '/*';
                                } elsif ($realfile =~ /\.(c|dts|dtsi)$/) {
                                        $comment = '//';
                                } elsif (($checklicenseline == 2) || $realfile =~ /\.(sh|pl|py|awk|tc)$/) {
                                        $comment = '#';
                                } elsif ($realfile =~ /\.rst$/) {
                                        $comment = '..';
                                }

                                if ($comment !~ /^$/ &&
                                    $rawline !~ /^\+\Q$comment\E SPDX-License-Identifier: /) {
                                        WARN("SPDX_LICENSE_TAG",
                                             "Missing or malformed SPDX-License-Identifier tag in line $checklicenseline\n" . $herecurr);
                                }
                        }
                }

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

# line length limit (with some exclusions)
#
# There are a few types of lines that may extend beyond $max_line_length:
#       logging functions like pr_info that end in a string
#       lines with a single string
#       #defines that are a single string
#       lines with an RFC3986 like URL
#
# There are 3 different line length message types:
# LONG_LINE_COMMENT     a comment starts before but extends beyond $max_line_length
# LONG_LINE_STRING      a string starts before but extends beyond $max_line_length
# LONG_LINE             all other lines longer than $max_line_length
#
# if LONG_LINE is ignored, the other 2 types are also ignored
#

                if ($line =~ /^\+/ && $length > $max_line_length) {
                        my $msg_type = "LONG_LINE";

                        # Check the allowed long line types first

                        # logging functions that end in a string that starts
                        # before $max_line_length
                        if ($line =~ /^\+\s*$logFunctions\s*\(\s*(?:(?:KERN_\S+\s*|[^"]*))?($String\s*(?:|,|\)\s*;)\s*)$/ &&
                            length(expand_tabs(substr($line, 1, length($line) - length($1) - 1))) <= $max_line_length) {
                                $msg_type = "";

                        # lines with only strings (w/ possible termination)
                        # #defines with only strings

                        } elsif ($line =~ /^\+\s*$String\s*(?:\s*|,|\)\s*;)\s*$/ ||
                                 $line =~ /^\+\s*#\s*define\s+\w+\s+$String$/) {
                                $msg_type = "";

                        # More special cases
                        } elsif ($line =~ /^\+.*\bEFI_GUID\s*\(/ ||
                                 $line =~ /^\+\s*(?:\w+)?\s*DEFINE_PER_CPU/) {
                                $msg_type = "";

                        # URL ($rawline is used in case the URL is in a comment)
                        } elsif ($rawline =~ /^\+.*\b[a-z][\w\.\+\-]*:\/\/\S+/i) {
                                $msg_type = "";

                        # Otherwise set the alternate message types

                        # a comment starts before $max_line_length
                        } elsif ($line =~ /($;[\s$;]*)$/ &&
                                 length(expand_tabs(substr($line, 1, length($line) - length($1) - 1))) <= $max_line_length) {
                                $msg_type = "LONG_LINE_COMMENT"

                        # a quoted string starts before $max_line_length
                        } elsif ($sline =~ /\s*($String(?:\s*(?:\\|,\s*|\)\s*;\s*))?)$/ &&
                                 length(expand_tabs(substr($line, 1, length($line) - length($1) - 1))) <= $max_line_length) {
                                $msg_type = "LONG_LINE_STRING"
                        }

                        if ($msg_type ne "" &&
                            (show_type("LONG_LINE") || show_type($msg_type))) {
                                WARN($msg_type,
                                     "line over $max_line_length characters\n" . $herecurr);
                        }
                }

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

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

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

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

# check for assignments on the start of a line
                if ($sline =~ /^\+\s+($Assignment)[^=]/) {
                        CHK("ASSIGNMENT_CONTINUATIONS",
                            "Assignment operator '$1' should be on the previous line\n" . $hereprev);
                }

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

# check indentation starts on a tab stop
                if ($^V && $^V ge 5.10.0 &&
                    $sline =~ /^\+\t+( +)(?:$c90_Keywords\b|\{\s*$|\}\s*(?:else\b|while\b|\s*$)|$Declare\s*$Ident\s*[;=])/) {
                        my $indent = length($1);
                        if ($indent % 8) {
                                if (WARN("TABSTOP",
                                         "Statements should start on a tabstop\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s@(^\+\t+) +@$1 . "\t" x ($indent/8)@e;
                                }
                        }
                }

# check multi-line statement indentation matches previous line
                if ($^V && $^V ge 5.10.0 &&
                    $prevline =~ /^\+([ \t]*)((?:$c90_Keywords(?:\s+if)\s*)|(?:$Declare\s*)?(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*|(?:\*\s*)*$Lval\s*=\s*$Ident\s*)\(.*(\&\&|\|\||,)\s*$/) {
                        $prevline =~ /^\+(\t*)(.*)$/;
                        my $oldindent = $1;
                        my $rest = $2;

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

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

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

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

# check for space after cast like "(int) foo" or "(struct foo) bar"
# avoid checking a few false positives:
#   "sizeof(<type>)" or "__alignof__(<type>)"
#   function pointer declarations like "(*foo)(int) = bar;"
#   structure definitions like "(struct foo) { 0 };"
#   multiline macros that define functions
#   known attributes or the __attribute__ keyword
                if ($line =~ /^\+(.*)\(\s*$Type\s*\)([ \t]++)((?![={]|\\$|$Attribute|__attribute__))/ &&
                    (!defined($1) || $1 !~ /\b(?:sizeof|__alignof__)\s*$/)) {
                        if (CHK("SPACING",
                                "No space is necessary after a cast\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~
                                    s/(\(\s*$Type\s*\))[ \t]+/$1/;
                        }
                }

# Block comment styles
# Networking with an initial /*
                if ($realfile =~ m@^(drivers/net/|net/)@ &&
                    $prevrawline =~ /^\+[ \t]*\/\*[ \t]*$/ &&
                    $rawline =~ /^\+[ \t]*\*/ &&
                    $realline > 2) {
                        WARN("NETWORKING_BLOCK_COMMENT_STYLE",
                             "networking block comments don't use an empty /* line, use /* Comment...\n" . $hereprev);
                }

# 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_COMMENT_STYLE",
                             "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_COMMENT_STYLE",
                             "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_COMMENT_STYLE",
                                     "Block comments should align the * on each line\n" . $hereprev);
                        }
                }

# check for missing blank lines after struct/union declarations
# with exceptions for various attributes and macros
                if ($prevline =~ /^[\+ ]};?\s*$/ &&
                    $line =~ /^\+/ &&
                    !($line =~ /^\+\s*$/ ||
                      $line =~ /^\+\s*EXPORT_SYMBOL/ ||
                      $line =~ /^\+\s*MODULE_/i ||
                      $line =~ /^\+\s*\#\s*(?:end|elif|else)/ ||
                      $line =~ /^\+[a-z_]*init/ ||
                      $line =~ /^\+\s*(?:static\s+)?[A-Z_]*ATTR/ ||
                      $line =~ /^\+\s*DECLARE/ ||
                      $line =~ /^\+\s*builtin_[\w_]*driver/ ||
                      $line =~ /^\+\s*__setup/)) {
                        if (CHK("LINE_SPACING",
                                "Please use a blank line after function/struct/union/enum declarations\n" . $hereprev) &&
                            $fix) {
                                fix_insert_line($fixlinenr, "\+");
                        }
                }

# check for multiple consecutive blank lines
                if ($prevline =~ /^[\+ ]\s*$/ &&
                    $line =~ /^\+\s*$/ &&
                    $last_blank_line != ($linenr - 1)) {
                        if (CHK("LINE_SPACING",
                                "Please don't use multiple blank lines\n" . $hereprev) &&
                            $fix) {
                                fix_delete_line($fixlinenr, $rawline);
                        }

                        $last_blank_line = $linenr;
                }

# check for missing blank lines after declarations
                if ($sline =~ /^\+\s+\S/ &&                     #Not at char 1
                        # actual declarations
                    ($prevline =~ /^\+\s+$Declare\s*$Ident\s*[=,;:\[]/ ||
                        # function pointer declarations
                     $prevline =~ /^\+\s+$Declare\s*\(\s*\*\s*$Ident\s*\)\s*[=,;:\[\(]/ ||
                        # foo bar; where foo is some local typedef or #define
                     $prevline =~ /^\+\s+$Ident(?:\s+|\s*\*\s*)$Ident\s*[=,;\[]/ ||
                        # known declaration macros
                     $prevline =~ /^\+\s+$declaration_macros/) &&
                        # for "else if" which can look like "$Ident $Ident"
                    !($prevline =~ /^\+\s+$c90_Keywords\b/ ||
                        # other possible extensions of declaration lines
                      $prevline =~ /(?:$Compare|$Assignment|$Operators)\s*$/ ||
                        # not starting a section or a macro "\" extended line
                      $prevline =~ /(?:\{\s*|\\)$/) &&
                        # looks like a declaration
                    !($sline =~ /^\+\s+$Declare\s*$Ident\s*[=,;:\[]/ ||
                        # function pointer declarations
                      $sline =~ /^\+\s+$Declare\s*\(\s*\*\s*$Ident\s*\)\s*[=,;:\[\(]/ ||
                        # foo bar; where foo is some local typedef or #define
                      $sline =~ /^\+\s+$Ident(?:\s+|\s*\*\s*)$Ident\s*[=,;\[]/ ||
                        # known declaration macros
                      $sline =~ /^\+\s+$declaration_macros/ ||
                        # start of struct or union or enum
                      $sline =~ /^\+\s+(?:union|struct|enum|typedef)\b/ ||
                        # start or end of block or continuation of declaration
                      $sline =~ /^\+\s+(?:$|[\{\}\.\#\"\?\:\(\[])/ ||
                        # bitfield continuation
                      $sline =~ /^\+\s+$Ident\s*:\s*\d+\s*[,;]/ ||
                        # other possible extensions of declaration lines
                      $sline =~ /^\+\s+\(?\s*(?:$Compare|$Assignment|$Operators)/) &&
                        # indentation of previous and current line are the same
                    (($prevline =~ /\+(\s+)\S/) && $sline =~ /^\+$1\S/)) {
                        if (WARN("LINE_SPACING",
                                 "Missing a blank line after declarations\n" . $hereprev) &&
                            $fix) {
                                fix_insert_line($fixlinenr, "\+");
                        }
                }

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

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

# check for unusual line ending [ or (
                if ($line =~ /^\+.*([\[\(])\s*$/) {
                        CHK("OPEN_ENDED_LINE",
                            "Lines should not end with a '$1'\n" . $herecurr);
                }

# check if this appears to be the start function declaration, save the name
                if ($sline =~ /^\+\{\s*$/ &&
                    $prevline =~ /^\+(?:(?:(?:$Storage|$Inline)\s*)*\s*$Type\s*)?($Ident)\(/) {
                        $context_function = $1;
                }

# check if this appears to be the end of function declaration
                if ($sline =~ /^\+\}\s*$/) {
                        undef $context_function;
                }

# check indentation of any line with a bare else
# (but not if it is a multiple line "if (foo) return bar; else return baz;")
# if the previous line is a break or return and is indented 1 tab more...
                if ($sline =~ /^\+([\t]+)(?:}[ \t]*)?else(?:[ \t]*{)?\s*$/) {
                        my $tabs = length($1) + 1;
                        if ($prevline =~ /^\+\t{$tabs,$tabs}break\b/ ||
                            ($prevline =~ /^\+\t{$tabs,$tabs}return\b/ &&
                             defined $lines[$linenr] &&
                             $lines[$linenr] !~ /^[ \+]\t{$tabs,$tabs}return/)) {
                                WARN("UNNECESSARY_ELSE",
                                     "else is not generally useful after a break or return\n" . $hereprev);
                        }
                }

# check indentation of a line with a break;
# if the previous line is a goto or return and is indented the same # of tabs
                if ($sline =~ /^\+([\t]+)break\s*;\s*$/) {
                        my $tabs = $1;
                        if ($prevline =~ /^\+$tabs(?:goto|return)\b/) {
                                WARN("UNNECESSARY_BREAK",
                                     "break is not useful after a goto or return\n" . $hereprev);
                        }
                }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                }

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

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

# if/while/etc brace do not go on next line, unless defining a do while loop,
# or if that brace on the next line is for something else
                if ($line =~ /(.*)\b((?:if|while|for|switch|(?:[a-z_]+|)for_each[a-z_]+)\s*\(|do\b|else\b)/ && $line !~ /^.\s*\#/) {
                        my $pre_ctx = "$1$2";

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

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

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

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

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

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

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

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

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

                        # remove inline comments
                        $s =~ s/$;/ /g;
                        $c =~ s/$;/ /g;

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

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

                        # 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 && $s ne '' &&
                            (($sindent % 8) != 0 ||
                             ($sindent < $indent) ||
                             ($sindent == $indent &&
                              ($s !~ /^\s*(?:\}|\{|else\b)/)) ||
                             ($sindent > $indent + 8))) {
                                WARN("SUSPECT_CODE_INDENT",
                                     "suspect code indent for conditional statements ($indent, $sindent)\n" . $herecurr . "$stat_real\n");
                        }
                }

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

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

# check for dereferences that span multiple lines
                if ($prevline =~ /^\+.*$Lval\s*(?:\.|->)\s*$/ &&
                    $line =~ /^\+\s*(?!\#\s*(?!define\s+|if))\s*$Lval/) {
                        $prevline =~ /($Lval\s*(?:\.|->))\s*$/;
                        my $ref = $1;
                        $line =~ /^.\s*($Lval)/;
                        $ref .= $1;
                        $ref =~ s/\s//g;
                        WARN("MULTILINE_DEREFERENCE",
                             "Avoid multiple line dereference - prefer '$ref'\n" . $hereprev);
                }

# check for declarations of signed or unsigned without int
                while ($line =~ m{\b($Declare)\s*(?!char\b|short\b|int\b|long\b)\s*($Ident)?\s*[=,;\[\)\(]}g) {
                        my $type = $1;
                        my $var = $2;
                        $var = "" if (!defined $var);
                        if ($type =~ /^(?:(?:$Storage|$Inline|$Attribute)\s+)*((?:un)?signed)((?:\s*\*)*)\s*$/) {
                                my $sign = $1;
                                my $pointer = $2;

                                $pointer = "" if (!defined $pointer);

                                if (WARN("UNSPECIFIED_INT",
                                         "Prefer '" . trim($sign) . " int" . rtrim($pointer) . "' to bare use of '$sign" . rtrim($pointer) . "'\n" . $herecurr) &&
                                    $fix) {
                                        my $decl = trim($sign) . " int ";
                                        my $comp_pointer = $pointer;
                                        $comp_pointer =~ s/\s//g;
                                        $decl .= $comp_pointer;
                                        $decl = rtrim($decl) if ($var eq "");
                                        $fixed[$fixlinenr] =~ s@\b$sign\s*\Q$pointer\E\s*$var\b@$decl$var@;
                                }
                        }
                }

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

# check for initialisation to aggregates open brace on the next line
                if ($line =~ /^.\s*{/ &&
                    $prevline =~ /(?:^|[^=])=\s*$/) {
                        if (ERROR("OPEN_BRACE",
                                  "that open brace { should be on the previous line\n" . $hereprev) &&
                            $fix && $prevline =~ /^\+/ && $line =~ /^\+/) {
                                fix_delete_line($fixlinenr - 1, $prevrawline);
                                fix_delete_line($fixlinenr, $rawline);
                                my $fixedline = $prevrawline;
                                $fixedline =~ s/\s*=\s*$/ = {/;
                                fix_insert_line($fixlinenr, $fixedline);
                                $fixedline = $line;
                                $fixedline =~ s/^(.\s*)\{\s*/$1/;
                                fix_insert_line($fixlinenr, $fixedline);
                        }
                }

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

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

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

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

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

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

# check for misordered declarations of char/short/int/long with signed/unsigned
                while ($sline =~ m{(\b$TypeMisordered\b)}g) {
                        my $tmp = trim($1);
                        WARN("MISORDERED_TYPE",
                             "type '$tmp' should be specified in [[un]signed] [short|int|long|long long] order\n" . $herecurr);
                }

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

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

# check for const <foo> const where <foo> is not a pointer or array type
                if ($sline =~ /\bconst\s+($BasicType)\s+const\b/) {
                        my $found = $1;
                        if ($sline =~ /\bconst\s+\Q$found\E\s+const\b\s*\*/) {
                                WARN("CONST_CONST",
                                     "'const $found const *' should probably be 'const $found * const'\n" . $herecurr);
                        } elsif ($sline !~ /\bconst\s+\Q$found\E\s+const\s+\w+\s*\[/) {
                                WARN("CONST_CONST",
                                     "'const $found const' should probably be 'const $found'\n" . $herecurr);
                        }
                }

# check for non-global char *foo[] = {"bar", ...} declarations.
                if ($line =~ /^.\s+(?:static\s+|const\s+)?char\s+\*\s*\w+\s*\[\s*\]\s*=\s*\{/) {
                        WARN("STATIC_CONST_CHAR_ARRAY",
                             "char * array declaration might be better as static const\n" .
                                $herecurr);
               }

# check for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo)
                if ($line =~ m@\bsizeof\s*\(\s*($Lval)\s*\)@) {
                        my $array = $1;
                        if ($line =~ m@\b(sizeof\s*\(\s*\Q$array\E\s*\)\s*/\s*sizeof\s*\(\s*\Q$array\E\s*\[\s*0\s*\]\s*\))@) {
                                my $array_div = $1;
                                if (WARN("ARRAY_SIZE",
                                         "Prefer ARRAY_SIZE($array)\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\Q$array_div\E/ARRAY_SIZE($array)/;
                                }
                        }
                }

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

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

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

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

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

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

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

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

# avoid BUG() or BUG_ON()
                if ($line =~ /\b(?:BUG|BUG_ON)\b/) {
                        my $msg_level = \&WARN;
                        $msg_level = \&CHK if ($file);
                        &{$msg_level}("AVOID_BUG",
                                      "Avoid crashing the kernel - try using WARN_ON & recovery code rather than BUG() or BUG_ON()\n" . $herecurr);
                }

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

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

# printk should use KERN_* levels
                if ($line =~ /\bprintk\s*\(\s*(?!KERN_[A-Z]+\b)/) {
                        WARN("PRINTK_WITHOUT_KERN_LEVEL",
                             "printk() should include KERN_<LEVEL> facility level\n" . $herecurr);
                }

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

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

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

# ENOSYS means "bad syscall nr" and nothing else.  This will have a small
# number of false positives, but assembly files are not checked, so at
# least the arch entry code will not trigger this warning.
                if ($line =~ /\bENOSYS\b/) {
                        WARN("ENOSYS",
                             "ENOSYS means 'invalid syscall nr' and nothing else\n" . $herecurr);
                }

# function brace can't be on same line, except for #defines of do while,
# or if closed on same line
                if ($^V && $^V ge 5.10.0 &&
                    $sline =~ /$Type\s*$Ident\s*$balanced_parens\s*\{/ &&
                    $sline !~ /\#\s*define\b.*do\s*\{/ &&
                    $sline !~ /}/) {
                        if (ERROR("OPEN_BRACE",
                                  "open brace '{' following function definitions go on the next line\n" . $herecurr) &&
                            $fix) {
                                fix_delete_line($fixlinenr, $rawline);
                                my $fixed_line = $rawline;
                                $fixed_line =~ /(^..*$Type\s*$Ident\(.*\)\s*){(.*)$/;
                                my $line1 = $1;
                                my $line2 = $2;
                                fix_insert_line($fixlinenr, ltrim($line1));
                                fix_insert_line($fixlinenr, "\+{");
                                if ($line2 !~ /^\s*$/) {
                                        fix_insert_line($fixlinenr, "\+\t" . trim($line2));
                                }
                        }
                }

# 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*$/) {
                        if (ERROR("OPEN_BRACE",
                                  "open brace '{' following $1 go on the same line\n" . $hereprev) &&
                            $fix && $prevline =~ /^\+/ && $line =~ /^\+/) {
                                fix_delete_line($fixlinenr - 1, $prevrawline);
                                fix_delete_line($fixlinenr, $rawline);
                                my $fixedline = rtrim($prevrawline) . " {";
                                fix_insert_line($fixlinenr, $fixedline);
                                $fixedline = $rawline;

                                $fixedline =~ s/^(.\s*)\{\s*/$1\t/;
                                if ($fixedline !~ /^\+\s*$/) {
                                        fix_insert_line($fixlinenr, $fixedline);
                                }
                        }
                }

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

# Function pointer declarations
# check spacing between type, funcptr, and args
# canonical declaration is "type (*funcptr)(args...)"
                if ($line =~ /^.\s*($Declare)\((\s*)\*(\s*)($Ident)(\s*)\)(\s*)\(/) {
                        my $declare = $1;
                        my $pre_pointer_space = $2;
                        my $post_pointer_space = $3;
                        my $funcname = $4;
                        my $post_funcname_space = $5;
                        my $pre_args_space = $6;

# the $Declare variable will capture all spaces after the type
# so check it for a missing trailing missing space but pointer return types
# don't need a space so don't warn for those.
                        my $post_declare_space = "";
                        if ($declare =~ /(\s+)$/) {
                                $post_declare_space = $1;
                                $declare = rtrim($declare);
                        }
                        if ($declare !~ /\*$/ && $post_declare_space =~ /^$/) {
                                WARN("SPACING",
                                     "missing space after return type\n" . $herecurr);
                                $post_declare_space = " ";
                        }

# unnecessary space "type  (*funcptr)(args...)"
# This test is not currently implemented because these declarations are
# equivalent to
#       int  foo(int bar, ...)
# and this is form shouldn't/doesn't generate a checkpatch warning.
#
#                       elsif ($declare =~ /\s{2,}$/) {
#                               WARN("SPACING",
#                                    "Multiple spaces after return type\n" . $herecurr);
#                       }

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

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

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

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

                        if (show_type("SPACING") && $fix) {
                                $fixed[$fixlinenr] =~
                                    s/^(.\s*)$Declare\s*\(\s*\*\s*$Ident\s*\)\s*\(/$1 . $declare . $post_declare_space . '(*' . $funcname . ')('/ex;
                        }
                }

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

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

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

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

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

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

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

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

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

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

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

                        $off = 0;

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

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

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

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

                                $off += length($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 !~ /^\\/ && $cc !~ /^;/) {
                                                if (ERROR("SPACING",
                                                          "space required after that '$op' $at\n" . $hereptr)) {
                                                        $good = $fix_elements[$n] . trim($fix_elements[$n + 1]) . " ";
                                                        $line_fixed = 1;
                                                }
                                        }

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

                                #   :   when part of a bitfield
                                } elsif ($opv eq ':B') {
                                        # skip the bitfield test for now

                                # No spaces for:
                                #   ->
                                } elsif ($op eq '->') {
                                        if ($ctx =~ /Wx.|.xW/) {
                                                if (ERROR("SPACING",
                                                          "spaces prohibited around that '$op' $at\n" . $hereptr)) {
                                                        $good = rtrim($fix_elements[$n]) . trim($fix_elements[$n + 1]);
                                                        if (defined $fix_elements[$n + 2]) {
                                                                $fix_elements[$n + 2] =~ s/^\s+//;
                                                        }
                                                        $line_fixed = 1;
                                                }
                                        }

                                # , must not have a space before and must have a space on the right.
                                } elsif ($op eq ',') {
                                        my $rtrim_before = 0;
                                        my $space_after = 0;
                                        if ($ctx =~ /Wx./) {
                                                if (ERROR("SPACING",
                                                          "space prohibited before that '$op' $at\n" . $hereptr)) {
                                                        $line_fixed = 1;
                                                        $rtrim_before = 1;
                                                }
                                        }
                                        if ($ctx !~ /.x[WEC]/ && $cc !~ /^}/) {
                                                if (ERROR("SPACING",
                                                          "space required after that '$op' $at\n" . $hereptr)) {
                                                        $line_fixed = 1;
                                                        $last_after = $n;
                                                        $space_after = 1;
                                                }
                                        }
                                        if ($rtrim_before || $space_after) {
                                                if ($rtrim_before) {
                                                        $good = rtrim($fix_elements[$n]) . trim($fix_elements[$n + 1]);
                                                } else {
                                                        $good = $fix_elements[$n] . trim($fix_elements[$n + 1]);
                                                }
                                                if ($space_after) {
                                                        $good .= " ";
                                                }
                                        }

                                # '*' 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' || $opv eq '&&U') {
                                        if ($ctx !~ /[WEBC]x./ && $ca !~ /(?:\)|!|~|\*|-|\&|\||\+\+|\-\-|\{)$/) {
                                                if (ERROR("SPACING",
                                                          "space required before that '$op' $at\n" . $hereptr)) {
                                                        if ($n != $last_after + 2) {
                                                                $good = $fix_elements[$n] . " " . ltrim($fix_elements[$n + 1]);
                                                                $line_fixed = 1;
                                                        }
                                                }
                                        }
                                        if ($op eq '*' && $cc =~/\s*$Modifier\b/) {
                                                # A unary '*' may be const

                                        } elsif ($ctx =~ /.xW/) {
                                                if (ERROR("SPACING",
                                                          "space prohibited after that '$op' $at\n" . $hereptr)) {
                                                        $good = $fix_elements[$n] . rtrim($fix_elements[$n + 1]);
                                                        if (defined $fix_elements[$n + 2]) {
                                                                $fix_elements[$n + 2] =~ s/^\s+//;
                                                        }
                                                        $line_fixed = 1;
                                                }
                                        }

                                # unary ++ and unary -- are allowed no space on one side.
                                } elsif ($op eq '++' or $op eq '--') {
                                        if ($ctx !~ /[WEOBC]x[^W]/ && $ctx !~ /[^W]x[WOBEC]/) {
                                                if (ERROR("SPACING",
                                                          "space required one side of that '$op' $at\n" . $hereptr)) {
                                                        $good = $fix_elements[$n] . trim($fix_elements[$n + 1]) . " ";
                                                        $line_fixed = 1;
                                                }
                                        }
                                        if ($ctx =~ /Wx[BE]/ ||
                                            ($ctx =~ /Wx./ && $cc =~ /^;/)) {
                                                if (ERROR("SPACING",
                                                          "space prohibited before that '$op' $at\n" . $hereptr)) {
                                                        $good = rtrim($fix_elements[$n]) . trim($fix_elements[$n + 1]);
                                                        $line_fixed = 1;
                                                }
                                        }
                                        if ($ctx =~ /ExW/) {
                                                if (ERROR("SPACING",
                                                          "space prohibited after that '$op' $at\n" . $hereptr)) {
                                                        $good = $fix_elements[$n] . trim($fix_elements[$n + 1]);
                                                        if (defined $fix_elements[$n + 2]) {
                                                                $fix_elements[$n + 2] =~ s/^\s+//;
                                                        }
                                                        $line_fixed = 1;
                                                }
                                        }

                                # << and >> may either have or not have spaces both sides
                                } elsif ($op eq '<<' or $op eq '>>' or
                                         $op eq '&' or $op eq '^' or $op eq '|' or
                                         $op eq '+' or $op eq '-' or
                                         $op eq '*' or $op eq '/' or
                                         $op eq '%')
                                {
                                        if ($check) {
                                                if (defined $fix_elements[$n + 2] && $ctx !~ /[EW]x[EW]/) {
                                                        if (CHK("SPACING",
                                                                "spaces preferred around that '$op' $at\n" . $hereptr)) {
                                                                $good = rtrim($fix_elements[$n]) . " " . trim($fix_elements[$n + 1]) . " ";
                                                                $fix_elements[$n + 2] =~ s/^\s+//;
                                                                $line_fixed = 1;
                                                        }
                                                } elsif (!defined $fix_elements[$n + 2] && $ctx !~ /Wx[OE]/) {
                                                        if (CHK("SPACING",
                                                                "space preferred before that '$op' $at\n" . $hereptr)) {
                                                                $good = rtrim($fix_elements[$n]) . " " . trim($fix_elements[$n + 1]);
                                                                $line_fixed = 1;
                                                        }
                                                }
                                        } elsif ($ctx =~ /Wx[^WCE]|[^WCE]xW/) {
                                                if (ERROR("SPACING",
                                                          "need consistent spacing around '$op' $at\n" . $hereptr)) {
                                                        $good = rtrim($fix_elements[$n]) . " " . trim($fix_elements[$n + 1]) . " ";
                                                        if (defined $fix_elements[$n + 2]) {
                                                                $fix_elements[$n + 2] =~ s/^\s+//;
                                                        }
                                                        $line_fixed = 1;
                                                }
                                        }

                                # 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./) {
                                                if (ERROR("SPACING",
                                                          "space prohibited before that '$op' $at\n" . $hereptr)) {
                                                        $good = rtrim($fix_elements[$n]) . trim($fix_elements[$n + 1]);
                                                        $line_fixed = 1;
                                                }
                                        }

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

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

                                        # for asm volatile statements
                                        # ignore a colon with another
                                        # colon immediately before or after
                                        if (($op eq ':') &&
                                            ($ca =~ /:$/ || $cc =~ /^:/)) {
                                                $ok = 1;
                                        }

                                        # messages are ERROR, but ?: are CHK
                                        if ($ok == 0) {
                                                my $msg_level = \&ERROR;
                                                $msg_level = \&CHK if (($op eq '?:' || $op eq '?' || $op eq ':') && $ctx =~ /VxV/);

                                                if (&{$msg_level}("SPACING",
                                                                  "spaces required around that '$op' $at\n" . $hereptr)) {
                                                        $good = rtrim($fix_elements[$n]) . " " . trim($fix_elements[$n + 1]) . " ";
                                                        if (defined $fix_elements[$n + 2]) {
                                                                $fix_elements[$n + 2] =~ s/^\s+//;
                                                        }
                                                        $line_fixed = 1;
                                                }
                                        }
                                }
                                $off += length($elements[$n + 1]);

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

                                $fixed_line = $fixed_line . $good;
                        }

                        if (($#elements % 2) == 0) {
                                $fixed_line = $fixed_line . $fix_elements[$#elements];
                        }

                        if ($fix && $line_fixed && $fixed_line ne $fixed[$fixlinenr]) {
                                $fixed[$fixlinenr] = $fixed_line;
                        }


                }

# check for whitespace before a non-naked semicolon
                if ($line =~ /^\+.*\S\s+;\s*$/) {
                        if (WARN("SPACING",
                                 "space prohibited before semicolon\n" . $herecurr) &&
                            $fix) {
                                1 while $fixed[$fixlinenr] =~
                                    s/^(\+.*\S)\s+;/$1;/;
                        }
                }

# check for multiple assignments
                if ($line =~ /^.\s*$Lval\s*=\s*$Lval\s*=(?!=)/) {
                        CHK("MULTIPLE_ASSIGNMENTS",
                            "multiple assignments should be avoided\n" . $herecurr);
                }

## # check for multiple declarations, allowing for a function declaration
## # continuation.
##              if ($line =~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Ident.*/ &&
##                  $line !~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Type\s*$Ident.*/) {
##
##                      # Remove any bracketed sections to ensure we do not
##                      # falsly report the parameters of functions.
##                      my $ln = $line;
##                      while ($ln =~ s/\([^\(\)]*\)//g) {
##                      }
##                      if ($ln =~ /,/) {
##                              WARN("MULTIPLE_DECLARATION",
##                                   "declaring multiple variables together should be avoided\n" . $herecurr);
##                      }
##              }

#need space before brace following if, while, etc
                if (($line =~ /\(.*\)\{/ && $line !~ /\($Type\)\{/) ||
                    $line =~ /do\{/) {
                        if (ERROR("SPACING",
                                  "space required before the open brace '{'\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/^(\+.*(?:do|\)))\{/$1 {/;
                        }
                }

## # check for blank lines before declarations
##              if ($line =~ /^.\t+$Type\s+$Ident(?:\s*=.*)?;/ &&
##                  $prevrawline =~ /^.\s*$/) {
##                      WARN("SPACING",
##                           "No blank lines before declarations\n" . $hereprev);
##              }
##

# closing brace should have a space following it when it has anything
# on the line
                if ($line =~ /}(?!(?:,|;|\)))\S/) {
                        if (ERROR("SPACING",
                                  "space required after that close brace '}'\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~
                                    s/}((?!(?:,|;|\)))\S)/} $1/;
                        }
                }

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

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

# check unnecessary parentheses around addressof/dereference single $Lvals
# ie: &(foo->bar) should be &foo->bar and *(foo->bar) should be *foo->bar

                while ($line =~ /(?:[^&]&\s*|\*)\(\s*($Ident\s*(?:$Member\s*)+)\s*\)/g) {
                        my $var = $1;
                        if (CHK("UNNECESSARY_PARENTHESES",
                                "Unnecessary parentheses around $var\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\(\s*\Q$var\E\s*\)/$var/;
                        }
                }

# check for unnecessary parentheses around function pointer uses
# ie: (foo->bar)(); should be foo->bar();
# but not "if (foo->bar) (" to avoid some false positives
                if ($line =~ /(\bif\s*|)(\(\s*$Ident\s*(?:$Member\s*)+\))[ \t]*\(/ && $1 !~ /^if/) {
                        my $var = $2;
                        if (CHK("UNNECESSARY_PARENTHESES",
                                "Unnecessary parentheses around function pointer $var\n" . $herecurr) &&
                            $fix) {
                                my $var2 = deparenthesize($var);
                                $var2 =~ s/\s//g;
                                $fixed[$fixlinenr] =~ s/\Q$var\E/$var2/;
                        }
                }

# check for unnecessary parentheses around comparisons in if uses
# when !drivers/staging or command-line uses --strict
                if (($realfile !~ m@^(?:drivers/staging/)@ || $check_orig) &&
                    $^V && $^V ge 5.10.0 && defined($stat) &&
                    $stat =~ /(^.\s*if\s*($balanced_parens))/) {
                        my $if_stat = $1;
                        my $test = substr($2, 1, -1);
                        my $herectx;
                        while ($test =~ /(?:^|[^\w\&\!\~])+\s*\(\s*([\&\!\~]?\s*$Lval\s*(?:$Compare\s*$FuncArg)?)\s*\)/g) {
                                my $match = $1;
                                # avoid parentheses around potential macro args
                                next if ($match =~ /^\s*\w+\s*$/);
                                if (!defined($herectx)) {
                                        $herectx = $here . "\n";
                                        my $cnt = statement_rawlines($if_stat);
                                        for (my $n = 0; $n < $cnt; $n++) {
                                                my $rl = raw_line($linenr, $n);
                                                $herectx .=  $rl . "\n";
                                                last if $rl =~ /^[ \+].*\{/;
                                        }
                                }
                                CHK("UNNECESSARY_PARENTHESES",
                                    "Unnecessary parentheses around '$match'\n" . $herectx);
                        }
                }

#goto labels aren't indented, allow a single space however
                if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
                   !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
                        if (WARN("INDENTED_LABEL",
                                 "labels should not be indented\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~
                                    s/^(.)\s+/$1/;
                        }
                }

# return is not a function
                if (defined($stat) && $stat =~ /^.\s*return(\s*)\(/s) {
                        my $spacing = $1;
                        if ($^V && $^V ge 5.10.0 &&
                            $stat =~ /^.\s*return\s*($balanced_parens)\s*;\s*$/) {
                                my $value = $1;
                                $value = deparenthesize($value);
                                if ($value =~ m/^\s*$FuncArg\s*(?:\?|$)/) {
                                        ERROR("RETURN_PARENTHESES",
                                              "return is not a function, parentheses are not required\n" . $herecurr);
                                }
                        } elsif ($spacing !~ /\s+/) {
                                ERROR("SPACING",
                                      "space required before the open parenthesis '('\n" . $herecurr);
                        }
                }

# unnecessary return in a void function
# at end-of-function, with the previous line a single leading tab, then return;
# and the line before that not a goto label target like "out:"
                if ($sline =~ /^[ \+]}\s*$/ &&
                    $prevline =~ /^\+\treturn\s*;\s*$/ &&
                    $linenr >= 3 &&
                    $lines[$linenr - 3] =~ /^[ +]/ &&
                    $lines[$linenr - 3] !~ /^[ +]\s*$Ident\s*:/) {
                        WARN("RETURN_VOID",
                             "void function return statements are not generally useful\n" . $hereprev);
               }

# if statements using unnecessary parentheses - ie: if ((foo == bar))
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /\bif\s*((?:\(\s*){2,})/) {
                        my $openparens = $1;
                        my $count = $openparens =~ tr@\(@\(@;
                        my $msg = "";
                        if ($line =~ /\bif\s*(?:\(\s*){$count,$count}$LvalOrFunc\s*($Compare)\s*$LvalOrFunc(?:\s*\)){$count,$count}/) {
                                my $comp = $4;  #Not $1 because of $LvalOrFunc
                                $msg = " - maybe == should be = ?" if ($comp eq "==");
                                WARN("UNNECESSARY_PARENTHESES",
                                     "Unnecessary parentheses$msg\n" . $herecurr);
                        }
                }

# comparisons with a constant or upper case identifier on the left
#       avoid cases like "foo + BAR < baz"
#       only fix matches surrounded by parentheses to avoid incorrect
#       conversions like "FOO < baz() + 5" being "misfixed" to "baz() > FOO + 5"
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /^\+(.*)\b($Constant|[A-Z_][A-Z0-9_]*)\s*($Compare)\s*($LvalOrFunc)/) {
                        my $lead = $1;
                        my $const = $2;
                        my $comp = $3;
                        my $to = $4;
                        my $newcomp = $comp;
                        if ($lead !~ /(?:$Operators|\.)\s*$/ &&
                            $to !~ /^(?:Constant|[A-Z_][A-Z0-9_]*)$/ &&
                            WARN("CONSTANT_COMPARISON",
                                 "Comparisons should place the constant on the right side of the test\n" . $herecurr) &&
                            $fix) {
                                if ($comp eq "<") {
                                        $newcomp = ">";
                                } elsif ($comp eq "<=") {
                                        $newcomp = ">=";
                                } elsif ($comp eq ">") {
                                        $newcomp = "<";
                                } elsif ($comp eq ">=") {
                                        $newcomp = "<=";
                                }
                                $fixed[$fixlinenr] =~ s/\(\s*\Q$const\E\s*$Compare\s*\Q$to\E\s*\)/($to $newcomp $const)/;
                        }
                }

# Return of what appears to be an errno should normally be negative
                if ($sline =~ /\breturn(?:\s*\(+\s*|\s+)(E[A-Z]+)(?:\s*\)+\s*|\s*)[;:,]/) {
                        my $name = $1;
                        if ($name ne 'EOF' && $name ne 'ERROR') {
                                WARN("USE_NEGATIVE_ERRNO",
                                     "return of an errno should typically be negative (ie: return -$1)\n" . $herecurr);
                        }
                }

# Need a space before open parenthesis after if, while etc
                if ($line =~ /\b(if|while|for|switch)\(/) {
                        if (ERROR("SPACING",
                                  "space required before the open parenthesis '('\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~
                                    s/\b(if|while|for|switch)\(/$1 \(/;
                        }
                }

# Check for illegal assignment in if conditional -- and check for trailing
# statements after the conditional.
                if ($line =~ /do\s*(?!{)/) {
                        ($stat, $cond, $line_nr_next, $remain_next, $off_next) =
                                ctx_statement_block($linenr, $realcnt, 0)
                                        if (!defined $stat);
                        my ($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} &&
                    defined($stat) && defined($cond) &&
                    $line =~ /\b(?:if|while|for)\s*\(/ && $line !~ /^.\s*#/) {
                        my ($s, $c) = ($stat, $cond);

                        if ($c =~ /\bif\s*\(.*[^<>!=]=[^=].*/s) {
                                ERROR("ASSIGN_IN_IF",
                                      "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",
                                      "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)
                {
                        WARN("HEXADECIMAL_BOOLEAN_TEST",
                             "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",
                                      "trailing statements should be on next line\n" . $herecurr);
                        }
                }
# if should not continue a brace
                if ($line =~ /}\s*if\b/) {
                        ERROR("TRAILING_STATEMENTS",
                              "trailing statements should be on next line (or did you mean 'else if'?)\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",
                              "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*/ &&
                    $previndent == $indent) {
                        if (ERROR("ELSE_AFTER_BRACE",
                                  "else should follow close brace '}'\n" . $hereprev) &&
                            $fix && $prevline =~ /^\+/ && $line =~ /^\+/) {
                                fix_delete_line($fixlinenr - 1, $prevrawline);
                                fix_delete_line($fixlinenr, $rawline);
                                my $fixedline = $prevrawline;
                                $fixedline =~ s/}\s*$//;
                                if ($fixedline !~ /^\+\s*$/) {
                                        fix_insert_line($fixlinenr, $fixedline);
                                }
                                $fixedline = $rawline;
                                $fixedline =~ s/^(.\s*)else/$1} else/;
                                fix_insert_line($fixlinenr, $fixedline);
                        }
                }

                if ($prevline=~/}\s*$/ and $line=~/^.\s*while\s*/ &&
                    $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*;/) {
                                if (ERROR("WHILE_AFTER_BRACE",
                                          "while should follow close brace '}'\n" . $hereprev) &&
                                    $fix && $prevline =~ /^\+/ && $line =~ /^\+/) {
                                        fix_delete_line($fixlinenr - 1, $prevrawline);
                                        fix_delete_line($fixlinenr, $rawline);
                                        my $fixedline = $prevrawline;
                                        my $trailing = $rawline;
                                        $trailing =~ s/^\+//;
                                        $trailing = trim($trailing);
                                        $fixedline =~ s/}\s*$/} $trailing/;
                                        fix_insert_line($fixlinenr, $fixedline);
                                }
                        }
                }

#Specific variable tests
                while ($line =~ m{($Constant|$Lval)}g) {
                        my $var = $1;

#gcc binary extension
                        if ($var =~ /^$Binary$/) {
                                if (WARN("GCC_BINARY_CONSTANT",
                                         "Avoid gcc v4.3+ binary constant extension: <$var>\n" . $herecurr) &&
                                    $fix) {
                                        my $hexval = sprintf("0x%x", oct($var));
                                        $fixed[$fixlinenr] =~
                                            s/\b$var\b/$hexval/;
                                }
                        }

#CamelCase
                        if ($var !~ /^$Constant$/ &&
                            $var =~ /[A-Z][a-z]|[a-z][A-Z]/ &&
#Ignore Page<foo> variants
                            $var !~ /^(?:Clear|Set|TestClear|TestSet|)Page[A-Z]/ &&
#Ignore SI style variants like nS, mV and dB (ie: max_uV, regulator_min_uA_show)
                            $var !~ /^(?:[a-z_]*?)_?[a-z][A-Z](?:_[a-z_]+)?$/ &&
#Ignore some three character SI units explicitly, like MiB and KHz
                            $var !~ /^(?:[a-z_]*?)_?(?:[KMGT]iB|[KMGT]?Hz)(?:_[a-z_]+)?$/) {
                                while ($var =~ m{($Ident)}g) {
                                        my $word = $1;
                                        next if ($word !~ /[A-Z][a-z]|[a-z][A-Z]/);
                                        if ($check) {
                                                seed_camelcase_includes();
                                                if (!$file && !$camelcase_file_seeded) {
                                                        seed_camelcase_file($realfile);
                                                        $camelcase_file_seeded = 1;
                                                }
                                        }
                                        if (!defined $camelcase{$word}) {
                                                $camelcase{$word} = 1;
                                                CHK("CAMELCASE",
                                                    "Avoid CamelCase: <$word>\n" . $herecurr);
                                        }
                                }
                        }
                }

#no spaces allowed after \ in define
                if ($line =~ /\#\s*define.*\\\s+$/) {
                        if (WARN("WHITESPACE_AFTER_LINE_CONTINUATION",
                                 "Whitespace after \\ makes next lines useless\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\s+$//;
                        }
                }

# warn if <asm/foo.h> is #included and <linux/foo.h> is available and includes
# itself <asm/foo.h> (uses RAW line)
                if ($tree && $rawline =~ m{^.\s*\#\s*include\s*\<asm\/(.*)\.h\>}) {
                        my $file = "$1.h";
                        my $checkfile = "include/linux/$file";
                        if (-f "$root/$checkfile" &&
                            $realfile ne $checkfile &&
                            $1 !~ /$allowed_asm_includes/)
                        {
                                my $asminclude = `grep -Ec "#include\\s+<asm/$file>" $root/$checkfile`;
                                if ($asminclude > 0) {
                                        if ($realfile =~ m{^arch/}) {
                                                CHK("ARCH_INCLUDE_LINUX",
                                                    "Consider using #include <linux/$file> instead of <asm/$file>\n" . $herecurr);
                                        } else {
                                                WARN("INCLUDE_LINUX",
                                                     "Use #include <linux/$file> instead of <asm/$file>\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 $has_flow_statement = 0;
                        my $has_arg_concat = 0;
                        ($dstat, $dcond, $ln, $cnt, $off) =
                                ctx_statement_block($linenr, $realcnt, 0);
                        $ctx = $dstat;
                        #print "dstat<$dstat> dcond<$dcond> cnt<$cnt> off<$off>\n";
                        #print "LINE<$lines[$ln-1]> len<" . length($lines[$ln-1]) . "\n";

                        $has_flow_statement = 1 if ($ctx =~ /\b(goto|return)\b/);
                        $has_arg_concat = 1 if ($ctx =~ /\#\#/ && $ctx !~ /\#\#\s*(?:__VA_ARGS__|args)\b/);

                        $dstat =~ s/^.\s*\#\s*define\s+$Ident(\([^\)]*\))?\s*//;
                        my $define_args = $1;
                        my $define_stmt = $dstat;
                        my @def_args = ();

                        if (defined $define_args && $define_args ne "") {
                                $define_args = substr($define_args, 1, length($define_args) - 2);
                                $define_args =~ s/\s*//g;
                                @def_args = split(",", $define_args);
                        }

                        $dstat =~ s/$;//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/)
                        {
                        }

                        # Flatten any obvious string concatentation.
                        while ($dstat =~ s/($String)\s*$Ident/$1/ ||
                               $dstat =~ s/$Ident\s*($String)/$1/)
                        {
                        }

                        # Make asm volatile uses seem like a generic function
                        $dstat =~ s/\b_*asm_*\s+_*volatile_*\b/asm_volatile/g;

                        my $exceptions = qr{
                                $Declare|
                                module_param_named|
                                MODULE_PARM_DESC|
                                DECLARE_PER_CPU|
                                DEFINE_PER_CPU|
                                __typeof__\(|
                                union|
                                struct|
                                \.$Ident\s*=\s*|
                                ^\"|\"$|
                                ^\[
                        }x;
                        #print "REST<$rest> dstat<$dstat> ctx<$ctx>\n";

                        $ctx =~ s/\n*$//;
                        my $stmt_cnt = statement_rawlines($ctx);
                        my $herectx = get_stat_here($linenr, $stmt_cnt, $here);

                        if ($dstat ne '' &&
                            $dstat !~ /^(?:$Ident|-?$Constant),$/ &&                    # 10, // foo(),
                            $dstat !~ /^(?:$Ident|-?$Constant);$/ &&                    # foo();
                            $dstat !~ /^[!~-]?(?:$Lval|$Constant)$/ &&          # 10 // foo() // !foo // ~foo // -foo // foo->bar // foo.bar->baz
                            $dstat !~ /^'X'$/ && $dstat !~ /^'XX'$/ &&                  # character constants
                            $dstat !~ /$exceptions/ &&

                            $dstat !~ /^\.$Ident\s*=/ &&                                # .foo =
                            $dstat !~ /^(?:\#\s*$Ident|\#\s*$Constant)\s*$/ &&          # stringification #foo
                            $dstat !~ /^do\s*$Constant\s*while\s*$Constant;?$/ &&       # do {...} while (...); // do {...} while (...)
                            $dstat !~ /^for\s*$Constant$/ &&                            # for (...)
                            $dstat !~ /^for\s*$Constant\s+(?:$Ident|-?$Constant)$/ &&   # for (...) bar()
                            $dstat !~ /^do\s*{/ &&                                      # do {...
                            $dstat !~ /^\(\{/ &&                                                # ({...
                            $ctx !~ /^.\s*#\s*define\s+TRACE_(?:SYSTEM|INCLUDE_FILE|INCLUDE_PATH)\b/)
                        {
                                if ($dstat =~ /^\s*if\b/) {
                                        ERROR("MULTISTATEMENT_MACRO_USE_DO_WHILE",
                                              "Macros starting with if should be enclosed by a do - while loop to avoid possible if/else logic defects\n" . "$herectx");
                                } elsif ($dstat =~ /;/) {
                                        ERROR("MULTISTATEMENT_MACRO_USE_DO_WHILE",
                                              "Macros with multiple statements should be enclosed in a do - while loop\n" . "$herectx");
                                } else {
                                        ERROR("COMPLEX_MACRO",
                                              "Macros with complex values should be enclosed in parentheses\n" . "$herectx");
                                }

                        }

                        # Make $define_stmt single line, comment-free, etc
                        my @stmt_array = split('\n', $define_stmt);
                        my $first = 1;
                        $define_stmt = "";
                        foreach my $l (@stmt_array) {
                                $l =~ s/\\$//;
                                if ($first) {
                                        $define_stmt = $l;
                                        $first = 0;
                                } elsif ($l =~ /^[\+ ]/) {
                                        $define_stmt .= substr($l, 1);
                                }
                        }
                        $define_stmt =~ s/$;//g;
                        $define_stmt =~ s/\s+/ /g;
                        $define_stmt = trim($define_stmt);

# check if any macro arguments are reused (ignore '...' and 'type')
                        foreach my $arg (@def_args) {
                                next if ($arg =~ /\.\.\./);
                                next if ($arg =~ /^type$/i);
                                my $tmp_stmt = $define_stmt;
                                $tmp_stmt =~ s/\b(typeof|__typeof__|__builtin\w+|typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)*\b//g;
                                $tmp_stmt =~ s/\#+\s*$arg\b//g;
                                $tmp_stmt =~ s/\b$arg\s*\#\#//g;
                                my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;
                                if ($use_cnt > 1) {
                                        CHK("MACRO_ARG_REUSE",
                                            "Macro argument reuse '$arg' - possible side-effects?\n" . "$herectx");
                                    }
# check if any macro arguments may have other precedence issues
                                if ($tmp_stmt =~ m/($Operators)?\s*\b$arg\b\s*($Operators)?/m &&
                                    ((defined($1) && $1 ne ',') ||
                                     (defined($2) && $2 ne ','))) {
                                        CHK("MACRO_ARG_PRECEDENCE",
                                            "Macro argument '$arg' may be better as '($arg)' to avoid precedence issues\n" . "$herectx");
                                }
                        }

# check for macros with flow control, but without ## concatenation
# ## concatenation is commonly a macro that defines a function so ignore those
                        if ($has_flow_statement && !$has_arg_concat) {
                                my $cnt = statement_rawlines($ctx);
                                my $herectx = get_stat_here($linenr, $cnt, $here);

                                WARN("MACRO_WITH_FLOW_CONTROL",
                                     "Macros with flow control statements should be avoided\n" . "$herectx");
                        }

# check for line continuations outside of #defines, preprocessor #, and asm

                } else {
                        if ($prevline !~ /^..*\\$/ &&
                            $line !~ /^\+\s*\#.*\\$/ &&         # preprocessor
                            $line !~ /^\+.*\b(__asm__|asm)\b.*\\$/ &&   # asm
                            $line =~ /^\+.*\\$/) {
                                WARN("LINE_CONTINUATIONS",
                                     "Avoid unnecessary line continuations\n" . $herecurr);
                        }
                }

# do {} while (0) macro tests:
# single-statement macros do not need to be enclosed in do while (0) loop,
# macro should not end with a semicolon
                if ($^V && $^V ge 5.10.0 &&
                    $realfile !~ m@/vmlinux.lds.h$@ &&
                    $line =~ /^.\s*\#\s*define\s+$Ident(\()?/) {
                        my $ln = $linenr;
                        my $cnt = $realcnt;
                        my ($off, $dstat, $dcond, $rest);
                        my $ctx = '';
                        ($dstat, $dcond, $ln, $cnt, $off) =
                                ctx_statement_block($linenr, $realcnt, 0);
                        $ctx = $dstat;

                        $dstat =~ s/\\\n.//g;
                        $dstat =~ s/$;/ /g;

                        if ($dstat =~ /^\+\s*#\s*define\s+$Ident\s*${balanced_parens}\s*do\s*{(.*)\s*}\s*while\s*\(\s*0\s*\)\s*([;\s]*)\s*$/) {
                                my $stmts = $2;
                                my $semis = $3;

                                $ctx =~ s/\n*$//;
                                my $cnt = statement_rawlines($ctx);
                                my $herectx = get_stat_here($linenr, $cnt, $here);

                                if (($stmts =~ tr/;/;/) == 1 &&
                                    $stmts !~ /^\s*(if|while|for|switch)\b/) {
                                        WARN("SINGLE_STATEMENT_DO_WHILE_MACRO",
                                             "Single statement macros should not use a do {} while (0) loop\n" . "$herectx");
                                }
                                if (defined $semis && $semis ne "") {
                                        WARN("DO_WHILE_MACRO_WITH_TRAILING_SEMICOLON",
                                             "do {} while (0) macros should not be semicolon terminated\n" . "$herectx");
                                }
                        } elsif ($dstat =~ /^\+\s*#\s*define\s+$Ident.*;\s*$/) {
                                $ctx =~ s/\n*$//;
                                my $cnt = statement_rawlines($ctx);
                                my $herectx = get_stat_here($linenr, $cnt, $here);

                                WARN("TRAILING_SEMICOLON",
                                     "macros should not use a trailing semicolon\n" . "$herectx");
                        }
                }

# check for redundant bracing round if etc
                if ($line =~ /(^.*)\bif\b/ && $1 !~ /else\s*$/) {
                        my ($level, $endln, @chunks) =
                                ctx_statement_full($linenr, $realcnt, 1);
                        #print "chunks<$#chunks> linenr<$linenr> endln<$endln> level<$level>\n";
                        #print "APW: <<$chunks[1][0]>><<$chunks[1][1]>>\n";
                        if ($#chunks > 0 && $level == 0) {
                                my @allowed = ();
                                my $allow = 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;

                                        $allowed[$allow] = 0;
                                        #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), '');

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

                                        #print "cond<$cond> block<$block> allowed<$allowed[$allow]>\n";
                                        if (statement_lines($cond) > 1) {
                                                #print "APW: ALLOWED: cond<$cond>\n";
                                                $allowed[$allow] = 1;
                                        }
                                        if ($block =~/\b(?:if|for|while)\b/) {
                                                #print "APW: ALLOWED: block<$block>\n";
                                                $allowed[$allow] = 1;
                                        }
                                        if (statement_block_size($block) > 1) {
                                                #print "APW: ALLOWED: lines block<$block>\n";
                                                $allowed[$allow] = 1;
                                        }
                                        $allow++;
                                }
                                if ($seen) {
                                        my $sum_allowed = 0;
                                        foreach (@allowed) {
                                                $sum_allowed += $_;
                                        }
                                        if ($sum_allowed == 0) {
                                                WARN("BRACES",
                                                     "braces {} are not necessary for any arm of this statement\n" . $herectx);
                                        } elsif ($sum_allowed != $allow &&
                                                 $seen != $allow) {
                                                CHK("BRACES",
                                                    "braces {} should be used on all arms of this statement\n" . $herectx);
                                        }
                                }
                        }
                }
                if (!defined $suppress_ifbraces{$linenr - 1} &&
                                        $line =~ /\b(if|while|for|else)\b/) {
                        my $allowed = 0;

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

                                WARN("BRACES",
                                     "braces {} are not necessary for single statement blocks\n" . $herectx);
                        }
                }

# check for single line unbalanced braces
                if ($sline =~ /^.\s*\}\s*else\s*$/ ||
                    $sline =~ /^.\s*else\s*\{\s*$/) {
                        CHK("BRACES", "Unbalanced braces around else statement\n" . $herecurr);
                }

# check for unnecessary blank lines around braces
                if (($line =~ /^.\s*}\s*$/ && $prevrawline =~ /^.\s*$/)) {
                        if (CHK("BRACES",
                                "Blank lines aren't necessary before a close brace '}'\n" . $hereprev) &&
                            $fix && $prevrawline =~ /^\+/) {
                                fix_delete_line($fixlinenr - 1, $prevrawline);
                        }
                }
                if (($rawline =~ /^.\s*$/ && $prevline =~ /^..*{\s*$/)) {
                        if (CHK("BRACES",
                                "Blank lines aren't necessary after an open brace '{'\n" . $hereprev) &&
                            $fix) {
                                fix_delete_line($fixlinenr, $rawline);
                        }
                }

# no volatiles please
                my $asm_volatile = qr{\b(__asm__|asm)\s+(__volatile__|volatile)\b};
                if ($line =~ /\bvolatile\b/ && $line !~ /$asm_volatile/) {
                        WARN("VOLATILE",
                             "Use of volatile is usually wrong: see Documentation/process/volatile-considered-harmful.rst\n" . $herecurr);
                }

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

                                fix_delete_line($fixlinenr - 1, $prevrawline);
                                fix_delete_line($fixlinenr, $rawline);
                                my $fixedline = $prevrawline;
                                $fixedline =~ s/"\s*$//;
                                $fixedline .= substr($extracted_string, 1) . trim($comma_close);
                                fix_insert_line($fixlinenr - 1, $fixedline);
                                $fixedline = $rawline;
                                $fixedline =~ s/\Q$extracted_string\E\Q$comma_close\E//;
                                if ($fixedline !~ /\+\s*$/) {
                                        fix_insert_line($fixlinenr, $fixedline);
                                }
                                $last_coalesced_string_linenr = $linenr;
                        }
                }

# check for missing a space in a string concatenation
                if ($prevrawline =~ /[^\\]\w"$/ && $rawline =~ /^\+[\t ]+"\w/) {
                        WARN('MISSING_SPACE',
                             "break quoted strings at a space character\n" . $hereprev);
                }

# check for an embedded function name in a string when the function is known
# This does not work very well for -f --file checking as it depends on patch
# context providing the function name or a single line form for in-file
# function declarations
                if ($line =~ /^\+.*$String/ &&
                    defined($context_function) &&
                    get_quoted_string($line, $rawline) =~ /\b$context_function\b/ &&
                    length(get_quoted_string($line, $rawline)) != (length($context_function) + 2)) {
                        WARN("EMBEDDED_FUNCTION_NAME",
                             "Prefer using '\"%s...\", __func__' to using '$context_function', this function's name, in a string\n" . $herecurr);
                }

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

                }

# concatenated string without spaces between elements
                if ($line =~ /$String[A-Z_]/ || $line =~ /[A-Za-z0-9_]$String/) {
                        CHK("CONCATENATED_STRING",
                            "Concatenated strings should use spaces between elements\n" . $herecurr);
                }

# uncoalesced string fragments
                if ($line =~ /$String\s*"/) {
                        WARN("STRING_FRAGMENTS",
                             "Consecutive strings are generally better as a single string\n" . $herecurr);
                }

# check for non-standard and hex prefixed decimal printf formats
                my $show_L = 1; #don't show the same defect twice
                my $show_Z = 1;
                while ($line =~ /(?:^|")([X\t]*)(?:"|$)/g) {
                        my $string = substr($rawline, $-[1], $+[1] - $-[1]);
                        $string =~ s/%%/__/g;
                        # check for %L
                        if ($show_L && $string =~ /%[\*\d\.\$]*L([diouxX])/) {
                                WARN("PRINTF_L",
                                     "\%L$1 is non-standard C, use %ll$1\n" . $herecurr);
                                $show_L = 0;
                        }
                        # check for %Z
                        if ($show_Z && $string =~ /%[\*\d\.\$]*Z([diouxX])/) {
                                WARN("PRINTF_Z",
                                     "%Z$1 is non-standard C, use %z$1\n" . $herecurr);
                                $show_Z = 0;
                        }
                        # check for 0x<decimal>
                        if ($string =~ /0x%[\*\d\.\$\Llzth]*[diou]/) {
                                ERROR("PRINTF_0XDECIMAL",
                                      "Prefixing 0x with decimal output is defective\n" . $herecurr);
                        }
                }

# check for line continuations in quoted strings with odd counts of "
                if ($rawline =~ /\\$/ && $sline =~ tr/"/"/ % 2) {
                        WARN("LINE_CONTINUATIONS",
                             "Avoid line continuations in quoted strings\n" . $herecurr);
                }

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

# check for needless "if (<foo>) fn(<foo>)" uses
                if ($prevline =~ /\bif\s*\(\s*($Lval)\s*\)/) {
                        my $tested = quotemeta($1);
                        my $expr = '\s*\(\s*' . $tested . '\s*\)\s*;';
                        if ($line =~ /\b(kfree|usb_free_urb|debugfs_remove(?:_recursive)?|(?:kmem_cache|mempool|dma_pool)_destroy)$expr/) {
                                my $func = $1;
                                if (WARN('NEEDLESS_IF',
                                         "$func(NULL) is safe and this check is probably not required\n" . $hereprev) &&
                                    $fix) {
                                        my $do_fix = 1;
                                        my $leading_tabs = "";
                                        my $new_leading_tabs = "";
                                        if ($lines[$linenr - 2] =~ /^\+(\t*)if\s*\(\s*$tested\s*\)\s*$/) {
                                                $leading_tabs = $1;
                                        } else {
                                                $do_fix = 0;
                                        }
                                        if ($lines[$linenr - 1] =~ /^\+(\t+)$func\s*\(\s*$tested\s*\)\s*;\s*$/) {
                                                $new_leading_tabs = $1;
                                                if (length($leading_tabs) + 1 ne length($new_leading_tabs)) {
                                                        $do_fix = 0;
                                                }
                                        } else {
                                                $do_fix = 0;
                                        }
                                        if ($do_fix) {
                                                fix_delete_line($fixlinenr - 1, $prevrawline);
                                                $fixed[$fixlinenr] =~ s/^\+$new_leading_tabs/\+$leading_tabs/;
                                        }
                                }
                        }
                }

# check for unnecessary "Out of Memory" messages
                if ($line =~ /^\+.*\b$logFunctions\s*\(/ &&
                    $prevline =~ /^[ \+]\s*if\s*\(\s*(\!\s*|NULL\s*==\s*)?($Lval)(\s*==\s*NULL\s*)?\s*\)/ &&
                    (defined $1 || defined $3) &&
                    $linenr > 3) {
                        my $testval = $2;
                        my $testline = $lines[$linenr - 3];

                        my ($s, $c) = ctx_statement_block($linenr - 3, $realcnt, 0);
#                       print("line: <$line>\nprevline: <$prevline>\ns: <$s>\nc: <$c>\n\n\n");

                        if ($s =~ /(?:^|\n)[ \+]\s*(?:$Type\s*)?\Q$testval\E\s*=\s*(?:\([^\)]*\)\s*)?\s*(?:devm_)?(?:[kv][czm]alloc(?:_node|_array)?\b|kstrdup|kmemdup|(?:dev_)?alloc_skb)/) {
                                WARN("OOM_MESSAGE",
                                     "Possible unnecessary 'out of memory' message\n" . $hereprev);
                        }
                }

# check for logging functions with KERN_<LEVEL>
                if ($line !~ /printk(?:_ratelimited|_once)?\s*\(/ &&
                    $line =~ /\b$logFunctions\s*\(.*\b(KERN_[A-Z]+)\b/) {
                        my $level = $1;
                        if (WARN("UNNECESSARY_KERN_LEVEL",
                                 "Possible unnecessary $level\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\s*$level\s*//;
                        }
                }

# check for logging continuations
                if ($line =~ /\bprintk\s*\(\s*KERN_CONT\b|\bpr_cont\s*\(/) {
                        WARN("LOGGING_CONTINUATION",
                             "Avoid logging continuation uses where feasible\n" . $herecurr);
                }

# check for mask then right shift without a parentheses
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /$LvalOrFunc\s*\&\s*($LvalOrFunc)\s*>>/ &&
                    $4 !~ /^\&/) { # $LvalOrFunc may be &foo, ignore if so
                        WARN("MASK_THEN_SHIFT",
                             "Possible precedence defect with mask then right shift - may need parentheses\n" . $herecurr);
                }

# check for pointer comparisons to NULL
                if ($^V && $^V ge 5.10.0) {
                        while ($line =~ /\b$LvalOrFunc\s*(==|\!=)\s*NULL\b/g) {
                                my $val = $1;
                                my $equal = "!";
                                $equal = "" if ($4 eq "!=");
                                if (CHK("COMPARISON_TO_NULL",
                                        "Comparison to NULL could be written \"${equal}${val}\"\n" . $herecurr) &&
                                            $fix) {
                                        $fixed[$fixlinenr] =~ s/\b\Q$val\E\s*(?:==|\!=)\s*NULL\b/$equal$val/;
                                }
                        }
                }

# check for bad placement of section $InitAttribute (e.g.: __initdata)
                if ($line =~ /(\b$InitAttribute\b)/) {
                        my $attr = $1;
                        if ($line =~ /^\+\s*static\s+(?:const\s+)?(?:$attr\s+)?($NonptrTypeWithAttr)\s+(?:$attr\s+)?($Ident(?:\[[^]]*\])?)\s*[=;]/) {
                                my $ptr = $1;
                                my $var = $2;
                                if ((($ptr =~ /\b(union|struct)\s+$attr\b/ &&
                                      ERROR("MISPLACED_INIT",
                                            "$attr should be placed after $var\n" . $herecurr)) ||
                                     ($ptr !~ /\b(union|struct)\s+$attr\b/ &&
                                      WARN("MISPLACED_INIT",
                                           "$attr should be placed after $var\n" . $herecurr))) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/(\bstatic\s+(?:const\s+)?)(?:$attr\s+)?($NonptrTypeWithAttr)\s+(?:$attr\s+)?($Ident(?:\[[^]]*\])?)\s*([=;])\s*/"$1" . trim(string_find_replace($2, "\\s*$attr\\s*", " ")) . " " . trim(string_find_replace($3, "\\s*$attr\\s*", "")) . " $attr" . ("$4" eq ";" ? ";" : " = ")/e;
                                }
                        }
                }

# check for $InitAttributeData (ie: __initdata) with const
                if ($line =~ /\bconst\b/ && $line =~ /($InitAttributeData)/) {
                        my $attr = $1;
                        $attr =~ /($InitAttributePrefix)(.*)/;
                        my $attr_prefix = $1;
                        my $attr_type = $2;
                        if (ERROR("INIT_ATTRIBUTE",
                                  "Use of const init definition must use ${attr_prefix}initconst\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~
                                    s/$InitAttributeData/${attr_prefix}initconst/;
                        }
                }

# check for $InitAttributeConst (ie: __initconst) without const
                if ($line !~ /\bconst\b/ && $line =~ /($InitAttributeConst)/) {
                        my $attr = $1;
                        if (ERROR("INIT_ATTRIBUTE",
                                  "Use of $attr requires a separate use of const\n" . $herecurr) &&
                            $fix) {
                                my $lead = $fixed[$fixlinenr] =~
                                    /(^\+\s*(?:static\s+))/;
                                $lead = rtrim($1);
                                $lead = "$lead " if ($lead !~ /^\+$/);
                                $lead = "${lead}const ";
                                $fixed[$fixlinenr] =~ s/(^\+\s*(?:static\s+))/$lead/;
                        }
                }

# check for __read_mostly with const non-pointer (should just be const)
                if ($line =~ /\b__read_mostly\b/ &&
                    $line =~ /($Type)\s*$Ident/ && $1 !~ /\*\s*$/ && $1 =~ /\bconst\b/) {
                        if (ERROR("CONST_READ_MOSTLY",
                                  "Invalid use of __read_mostly with const type\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\s+__read_mostly\b//;
                        }
                }

# don't use __constant_<foo> functions outside of include/uapi/
                if ($realfile !~ m@^include/uapi/@ &&
                    $line =~ /(__constant_(?:htons|ntohs|[bl]e(?:16|32|64)_to_cpu|cpu_to_[bl]e(?:16|32|64)))\s*\(/) {
                        my $constant_func = $1;
                        my $func = $constant_func;
                        $func =~ s/^__constant_//;
                        if (WARN("CONSTANT_CONVERSION",
                                 "$constant_func should be $func\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\b$constant_func\b/$func/g;
                        }
                }

# prefer usleep_range over udelay
                if ($line =~ /\budelay\s*\(\s*(\d+)\s*\)/) {
                        my $delay = $1;
                        # ignore udelay's < 10, however
                        if (! ($delay < 10) ) {
                                CHK("USLEEP_RANGE",
                                    "usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt\n" . $herecurr);
                        }
                        if ($delay > 2000) {
                                WARN("LONG_UDELAY",
                                     "long udelay - prefer mdelay; see arch/arm/include/asm/delay.h\n" . $herecurr);
                        }
                }

# warn about unexpectedly long msleep's
                if ($line =~ /\bmsleep\s*\((\d+)\);/) {
                        if ($1 < 20) {
                                WARN("MSLEEP",
                                     "msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.txt\n" . $herecurr);
                        }
                }

# check for comparisons of jiffies
                if ($line =~ /\bjiffies\s*$Compare|$Compare\s*jiffies\b/) {
                        WARN("JIFFIES_COMPARISON",
                             "Comparing jiffies is almost always wrong; prefer time_after, time_before and friends\n" . $herecurr);
                }

# check for comparisons of get_jiffies_64()
                if ($line =~ /\bget_jiffies_64\s*\(\s*\)\s*$Compare|$Compare\s*get_jiffies_64\s*\(\s*\)/) {
                        WARN("JIFFIES_COMPARISON",
                             "Comparing get_jiffies_64() is almost always wrong; prefer time_after64, time_before64 and friends\n" . $herecurr);
                }

# 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+/) {
                        if (ERROR("SPACING",
                                  "exactly one space required after that #$1\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~
                                    s/^(.\s*\#\s*(ifdef|ifndef|elif))\s{2,}/$1 /;
                        }

                }

# check for spinlock_t definitions without a comment.
                if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/ ||
                    $line =~ /^.\s*(DEFINE_MUTEX)\s*\(/) {
                        my $which = $1;
                        if (!ctx_has_comment($first_line, $linenr)) {
                                CHK("UNCOMMENTED_DEFINITION",
                                    "$1 definition without comment\n" . $herecurr);
                        }
                }
# check for memory barriers without a comment.

                my $barriers = qr{
                        mb|
                        rmb|
                        wmb|
                        read_barrier_depends
                }x;
                my $barrier_stems = qr{
                        mb__before_atomic|
                        mb__after_atomic|
                        store_release|
                        load_acquire|
                        store_mb|
                        (?:$barriers)
                }x;
                my $all_barriers = qr{
                        (?:$barriers)|
                        smp_(?:$barrier_stems)|
                        virt_(?:$barrier_stems)
                }x;

                if ($line =~ /\b(?:$all_barriers)\s*\(/) {
                        if (!ctx_has_comment($first_line, $linenr)) {
                                WARN("MEMORY_BARRIER",
                                     "memory barrier without comment\n" . $herecurr);
                        }
                }

                my $underscore_smp_barriers = qr{__smp_(?:$barrier_stems)}x;

                if ($realfile !~ m@^include/asm-generic/@ &&
                    $realfile !~ m@/barrier\.h$@ &&
                    $line =~ m/\b(?:$underscore_smp_barriers)\s*\(/ &&
                    $line !~ m/^.\s*\#\s*define\s+(?:$underscore_smp_barriers)\s*\(/) {
                        WARN("MEMORY_BARRIER",
                             "__smp memory barriers shouldn't be used outside barrier.h and asm-generic\n" . $herecurr);
                }

# check for waitqueue_active without a comment.
                if ($line =~ /\bwaitqueue_active\s*\(/) {
                        if (!ctx_has_comment($first_line, $linenr)) {
                                WARN("WAITQUEUE_ACTIVE",
                                     "waitqueue_active without comment\n" . $herecurr);
                        }
                }

# check for smp_read_barrier_depends and read_barrier_depends
                if (!$file && $line =~ /\b(smp_|)read_barrier_depends\s*\(/) {
                        WARN("READ_BARRIER_DEPENDS",
                             "$1read_barrier_depends should only be used in READ_ONCE or DEC Alpha code\n" . $herecurr);
                }

# check of hardware specific defines
                if ($line =~ m@^.\s*\#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@ && $realfile !~ m@include/asm-@) {
                        CHK("ARCH_DEFINES",
                            "architecture specific defines should be avoided\n" .  $herecurr);
                }

# check that the storage class is not after a type
                if ($line =~ /\b($Type)\s+($Storage)\b/) {
                        WARN("STORAGE_CLASS",
                             "storage class '$2' should be located before type '$1'\n" . $herecurr);
                }
# Check that the storage class is at the beginning of a declaration
                if ($line =~ /\b$Storage\b/ &&
                    $line !~ /^.\s*$Storage/ &&
                    $line =~ /^.\s*(.+?)\$Storage\s/ &&
                    $1 !~ /[\,\)]\s*$/) {
                        WARN("STORAGE_CLASS",
                             "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_LOCATION",
                              "inline keyword should sit between storage class and type\n" . $herecurr);
                }

# Check for __inline__ and __inline, prefer inline
                if ($realfile !~ m@\binclude/uapi/@ &&
                    $line =~ /\b(__inline__|__inline)\b/) {
                        if (WARN("INLINE",
                                 "plain inline is preferred over $1\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\b(__inline__|__inline)\b/inline/;

                        }
                }

# Check for __attribute__ packed, prefer __packed
                if ($realfile !~ m@\binclude/uapi/@ &&
                    $line =~ /\b__attribute__\s*\(\s*\(.*\bpacked\b/) {
                        WARN("PREFER_PACKED",
                             "__packed is preferred over __attribute__((packed))\n" . $herecurr);
                }

# Check for __attribute__ aligned, prefer __aligned
                if ($realfile !~ m@\binclude/uapi/@ &&
                    $line =~ /\b__attribute__\s*\(\s*\(.*aligned/) {
                        WARN("PREFER_ALIGNED",
                             "__aligned(size) is preferred over __attribute__((aligned(size)))\n" . $herecurr);
                }

# Check for __attribute__ format(printf, prefer __printf
                if ($realfile !~ m@\binclude/uapi/@ &&
                    $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf/) {
                        if (WARN("PREFER_PRINTF",
                                 "__printf(string-index, first-to-check) is preferred over __attribute__((format(printf, string-index, first-to-check)))\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.*)\)\s*\)\s*\)/"__printf(" . trim($1) . ")"/ex;

                        }
                }

# Check for __attribute__ format(scanf, prefer __scanf
                if ($realfile !~ m@\binclude/uapi/@ &&
                    $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\b/) {
                        if (WARN("PREFER_SCANF",
                                 "__scanf(string-index, first-to-check) is preferred over __attribute__((format(scanf, string-index, first-to-check)))\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*scanf\s*,\s*(.*)\)\s*\)\s*\)/"__scanf(" . trim($1) . ")"/ex;
                        }
                }

# Check for __attribute__ weak, or __weak declarations (may have link issues)
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /(?:$Declare|$DeclareMisordered)\s*$Ident\s*$balanced_parens\s*(?:$Attribute)?\s*;/ &&
                    ($line =~ /\b__attribute__\s*\(\s*\(.*\bweak\b/ ||
                     $line =~ /\b__weak\b/)) {
                        ERROR("WEAK_DECLARATION",
                              "Using weak declarations can have unintended link defects\n" . $herecurr);
                }

# check for c99 types like uint8_t used outside of uapi/ and tools/
                if ($realfile !~ m@\binclude/uapi/@ &&
                    $realfile !~ m@\btools/@ &&
                    $line =~ /\b($Declare)\s*$Ident\s*[=;,\[]/) {
                        my $type = $1;
                        if ($type =~ /\b($typeC99Typedefs)\b/) {
                                $type = $1;
                                my $kernel_type = 'u';
                                $kernel_type = 's' if ($type =~ /^_*[si]/);
                                $type =~ /(\d+)/;
                                $kernel_type .= $1;
                                if (CHK("PREFER_KERNEL_TYPES",
                                        "Prefer kernel type '$kernel_type' over '$type'\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\b$type\b/$kernel_type/;
                                }
                        }
                }

# check for cast of C90 native int or longer types constants
                if ($line =~ /(\(\s*$C90_int_types\s*\)\s*)($Constant)\b/) {
                        my $cast = $1;
                        my $const = $2;
                        if (WARN("TYPECAST_INT_CONSTANT",
                                 "Unnecessary typecast of c90 int constant\n" . $herecurr) &&
                            $fix) {
                                my $suffix = "";
                                my $newconst = $const;
                                $newconst =~ s/${Int_type}$//;
                                $suffix .= 'U' if ($cast =~ /\bunsigned\b/);
                                if ($cast =~ /\blong\s+long\b/) {
                                        $suffix .= 'LL';
                                } elsif ($cast =~ /\blong\b/) {
                                        $suffix .= 'L';
                                }
                                $fixed[$fixlinenr] =~ s/\Q$cast\E$const\b/$newconst$suffix/;
                        }
                }

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

# check for sizeof without parenthesis
                if ($line =~ /\bsizeof\s+((?:\*\s*|)$Lval|$Type(?:\s+$Lval|))/) {
                        if (WARN("SIZEOF_PARENTHESIS",
                                 "sizeof $1 should be sizeof($1)\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\bsizeof\s+((?:\*\s*|)$Lval|$Type(?:\s+$Lval|))/"sizeof(" . trim($1) . ")"/ex;
                        }
                }

# check for struct spinlock declarations
                if ($line =~ /^.\s*\bstruct\s+spinlock\s+\w+\s*;/) {
                        WARN("USE_SPINLOCK_T",
                             "struct spinlock should be spinlock_t\n" . $herecurr);
                }

# check for seq_printf uses that could be seq_puts
                if ($sline =~ /\bseq_printf\s*\(.*"\s*\)\s*;\s*$/) {
                        my $fmt = get_quoted_string($line, $rawline);
                        $fmt =~ s/%%//g;
                        if ($fmt !~ /%/) {
                                if (WARN("PREFER_SEQ_PUTS",
                                         "Prefer seq_puts to seq_printf\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\bseq_printf\b/seq_puts/;
                                }
                        }
                }

# check for vsprintf extension %p<foo> misuses
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^\+(?![^\{]*\{\s*).*\b(\w+)\s*\(.*$String\s*,/s &&
                    $1 !~ /^_*volatile_*$/) {
                        my $stat_real;

                        my $lc = $stat =~ tr@\n@@;
                        $lc = $lc + $linenr;
                        for (my $count = $linenr; $count <= $lc; $count++) {
                                my $specifier;
                                my $extension;
                                my $bad_specifier = "";
                                my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0));
                                $fmt =~ s/%%//g;

                                while ($fmt =~ /(\%[\*\d\.]*p(\w))/g) {
                                        $specifier = $1;
                                        $extension = $2;
                                        if ($extension !~ /[SsBKRraEhMmIiUDdgVCbGNOx]/) {
                                                $bad_specifier = $specifier;
                                                last;
                                        }
                                        if ($extension eq "x" && !defined($stat_real)) {
                                                if (!defined($stat_real)) {
                                                        $stat_real = get_stat_real($linenr, $lc);
                                                }
                                                WARN("VSPRINTF_SPECIFIER_PX",
                                                     "Using vsprintf specifier '\%px' potentially exposes the kernel memory layout, if you don't really need the address please consider using '\%p'.\n" . "$here\n$stat_real\n");
                                        }
                                }
                                if ($bad_specifier ne "") {
                                        my $stat_real = get_stat_real($linenr, $lc);
                                        my $ext_type = "Invalid";
                                        my $use = "";
                                        if ($bad_specifier =~ /p[Ff]/) {
                                                $ext_type = "Deprecated";
                                                $use = " - use %pS instead";
                                                $use =~ s/pS/ps/ if ($bad_specifier =~ /pf/);
                                        }

                                        WARN("VSPRINTF_POINTER_EXTENSION",
                                             "$ext_type vsprintf pointer extension '$bad_specifier'$use\n" . "$here\n$stat_real\n");
                                }
                        }
                }

# Check for misused memsets
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*$FuncArg\s*\)/) {

                        my $ms_addr = $2;
                        my $ms_val = $7;
                        my $ms_size = $12;

                        if ($ms_size =~ /^(0x|)0$/i) {
                                ERROR("MEMSET",
                                      "memset to 0's uses 0 as the 2nd argument, not the 3rd\n" . "$here\n$stat\n");
                        } elsif ($ms_size =~ /^(0x|)1$/i) {
                                WARN("MEMSET",
                                     "single byte memset is suspicious. Swapped 2nd/3rd argument?\n" . "$here\n$stat\n");
                        }
                }

# Check for memcpy(foo, bar, ETH_ALEN) that could be ether_addr_copy(foo, bar)
#               if ($^V && $^V ge 5.10.0 &&
#                   defined $stat &&
#                   $stat =~ /^\+(?:.*?)\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {
#                       if (WARN("PREFER_ETHER_ADDR_COPY",
#                                "Prefer ether_addr_copy() over memcpy() if the Ethernet addresses are __aligned(2)\n" . "$here\n$stat\n") &&
#                           $fix) {
#                               $fixed[$fixlinenr] =~ s/\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/ether_addr_copy($2, $7)/;
#                       }
#               }

# Check for memcmp(foo, bar, ETH_ALEN) that could be ether_addr_equal*(foo, bar)
#               if ($^V && $^V ge 5.10.0 &&
#                   defined $stat &&
#                   $stat =~ /^\+(?:.*?)\bmemcmp\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {
#                       WARN("PREFER_ETHER_ADDR_EQUAL",
#                            "Prefer ether_addr_equal() or ether_addr_equal_unaligned() over memcmp()\n" . "$here\n$stat\n")
#               }

# check for memset(foo, 0x0, ETH_ALEN) that could be eth_zero_addr
# check for memset(foo, 0xFF, ETH_ALEN) that could be eth_broadcast_addr
#               if ($^V && $^V ge 5.10.0 &&
#                   defined $stat &&
#                   $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {
#
#                       my $ms_val = $7;
#
#                       if ($ms_val =~ /^(?:0x|)0+$/i) {
#                               if (WARN("PREFER_ETH_ZERO_ADDR",
#                                        "Prefer eth_zero_addr over memset()\n" . "$here\n$stat\n") &&
#                                   $fix) {
#                                       $fixed[$fixlinenr] =~ s/\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*,\s*ETH_ALEN\s*\)/eth_zero_addr($2)/;
#                               }
#                       } elsif ($ms_val =~ /^(?:0xff|255)$/i) {
#                               if (WARN("PREFER_ETH_BROADCAST_ADDR",
#                                        "Prefer eth_broadcast_addr() over memset()\n" . "$here\n$stat\n") &&
#                                   $fix) {
#                                       $fixed[$fixlinenr] =~ s/\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*,\s*ETH_ALEN\s*\)/eth_broadcast_addr($2)/;
#                               }
#                       }
#               }

# typecasts on min/max could be min_t/max_t
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^\+(?:.*?)\b(min|max)\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\)/) {
                        if (defined $2 || defined $7) {
                                my $call = $1;
                                my $cast1 = deparenthesize($2);
                                my $arg1 = $3;
                                my $cast2 = deparenthesize($7);
                                my $arg2 = $8;
                                my $cast;

                                if ($cast1 ne "" && $cast2 ne "" && $cast1 ne $cast2) {
                                        $cast = "$cast1 or $cast2";
                                } elsif ($cast1 ne "") {
                                        $cast = $cast1;
                                } else {
                                        $cast = $cast2;
                                }
                                WARN("MINMAX",
                                     "$call() should probably be ${call}_t($cast, $arg1, $arg2)\n" . "$here\n$stat\n");
                        }
                }

# check usleep_range arguments
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^\+(?:.*?)\busleep_range\s*\(\s*($FuncArg)\s*,\s*($FuncArg)\s*\)/) {
                        my $min = $1;
                        my $max = $7;
                        if ($min eq $max) {
                                WARN("USLEEP_RANGE",
                                     "usleep_range should not use min == max args; see Documentation/timers/timers-howto.txt\n" . "$here\n$stat\n");
                        } elsif ($min =~ /^\d+$/ && $max =~ /^\d+$/ &&
                                 $min > $max) {
                                WARN("USLEEP_RANGE",
                                     "usleep_range args reversed, use min then max; see Documentation/timers/timers-howto.txt\n" . "$here\n$stat\n");
                        }
                }

# check for naked sscanf
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $line =~ /\bsscanf\b/ &&
                    ($stat !~ /$Ident\s*=\s*sscanf\s*$balanced_parens/ &&
                     $stat !~ /\bsscanf\s*$balanced_parens\s*(?:$Compare)/ &&
                     $stat !~ /(?:$Compare)\s*\bsscanf\s*$balanced_parens/)) {
                        my $lc = $stat =~ tr@\n@@;
                        $lc = $lc + $linenr;
                        my $stat_real = get_stat_real($linenr, $lc);
                        WARN("NAKED_SSCANF",
                             "unchecked sscanf return value\n" . "$here\n$stat_real\n");
                }

# check for simple sscanf that should be kstrto<foo>
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $line =~ /\bsscanf\b/) {
                        my $lc = $stat =~ tr@\n@@;
                        $lc = $lc + $linenr;
                        my $stat_real = get_stat_real($linenr, $lc);
                        if ($stat_real =~ /\bsscanf\b\s*\(\s*$FuncArg\s*,\s*("[^"]+")/) {
                                my $format = $6;
                                my $count = $format =~ tr@%@%@;
                                if ($count == 1 &&
                                    $format =~ /^"\%(?i:ll[udxi]|[udxi]ll|ll|[hl]h?[udxi]|[udxi][hl]h?|[hl]h?|[udxi])"$/) {
                                        WARN("SSCANF_TO_KSTRTO",
                                             "Prefer kstrto<type> to single variable sscanf\n" . "$here\n$stat_real\n");
                                }
                        }
                }

# check for new externs in .h files.
                if ($realfile =~ /\.h$/ &&
                    $line =~ /^\+\s*(extern\s+)$Type\s*$Ident\s*\(/s) {
                        if (CHK("AVOID_EXTERNS",
                                "extern prototypes should be avoided in .h files\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/(.*)\bextern\b\s*(.*)/$1$2/;
                        }
                }

# 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')
                        {
                                WARN("AVOID_EXTERNS",
                                     "externs should be avoided in .c files\n" .  $herecurr);
                        }

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

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

# check for function declarations that have arguments without identifier names
                if (defined $stat &&
                    $stat =~ /^.\s*(?:extern\s+)?$Type\s*(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*\(\s*([^{]+)\s*\)\s*;/s &&
                    $1 ne "void") {
                        my $args = trim($1);
                        while ($args =~ m/\s*($Type\s*(?:$Ident|\(\s*\*\s*$Ident?\s*\)\s*$balanced_parens)?)/g) {
                                my $arg = trim($1);
                                if ($arg =~ /^$Type$/ && $arg !~ /enum\s+$Ident$/) {
                                        WARN("FUNCTION_ARGUMENTS",
                                             "function definition argument '$arg' should also have an identifier name\n" . $herecurr);
                                }
                        }
                }

# check for function definitions
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^.\s*(?:$Storage\s+)?$Type\s*($Ident)\s*$balanced_parens\s*{/s) {
                        $context_function = $1;

# check for multiline function definition with misplaced open brace
                        my $ok = 0;
                        my $cnt = statement_rawlines($stat);
                        my $herectx = $here . "\n";
                        for (my $n = 0; $n < $cnt; $n++) {
                                my $rl = raw_line($linenr, $n);
                                $herectx .=  $rl . "\n";
                                $ok = 1 if ($rl =~ /^[ \+]\{/);
                                $ok = 1 if ($rl =~ /\{/ && $n == 0);
                                last if $rl =~ /^[ \+].*\{/;
                        }
                        if (!$ok) {
                                ERROR("OPEN_BRACE",
                                      "open brace '{' following function definitions go on the next line\n" . $herectx);
                        }
                }

# checks for new __setup's
                if ($rawline =~ /\b__setup\("([^"]*)"/) {
                        my $name = $1;

                        if (!grep(/$name/, @setup_docs)) {
                                CHK("UNDOCUMENTED_SETUP",
                                    "__setup appears un-documented -- check Documentation/admin-guide/kernel-parameters.rst\n" . $herecurr);
                        }
                }

# check for pointless casting of kmalloc return
                if ($line =~ /\*\s*\)\s*[kv][czm]alloc(_node){0,1}\b/) {
                        WARN("UNNECESSARY_CASTS",
                             "unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);
                }

# alloc style
# p = alloc(sizeof(struct foo), ...) should be p = alloc(sizeof(*p), ...)
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*([kv][mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) {
                        CHK("ALLOC_SIZEOF_STRUCT",
                            "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr);
                }

# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^\+\s*($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)\s*,/) {
                        my $oldfunc = $3;
                        my $a1 = $4;
                        my $a2 = $10;
                        my $newfunc = "kmalloc_array";
                        $newfunc = "kcalloc" if ($oldfunc eq "kzalloc");
                        my $r1 = $a1;
                        my $r2 = $a2;
                        if ($a1 =~ /^sizeof\s*\S/) {
                                $r1 = $a2;
                                $r2 = $a1;
                        }
                        if ($r1 !~ /^sizeof\b/ && $r2 =~ /^sizeof\s*\S/ &&
                            !($r1 =~ /^$Constant$/ || $r1 =~ /^[A-Z_][A-Z0-9_]*$/)) {
                                my $cnt = statement_rawlines($stat);
                                my $herectx = get_stat_here($linenr, $cnt, $here);

                                if (WARN("ALLOC_WITH_MULTIPLY",
                                         "Prefer $newfunc over $oldfunc with multiply\n" . $herectx) &&
                                    $cnt == 1 &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' = ' . "$newfunc(" . trim($r1) . ', ' . trim($r2)/e;
                                }
                        }
                }

# check for krealloc arg reuse
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*\1\s*,/) {
                        WARN("KREALLOC_ARG_REUSE",
                             "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
                }

# check for alloc argument mismatch
                if ($line =~ /\b(kcalloc|kmalloc_array)\s*\(\s*sizeof\b/) {
                        WARN("ALLOC_ARRAY_ARGS",
                             "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
                }

# check for multiple semicolons
                if ($line =~ /;\s*;\s*$/) {
                        if (WARN("ONE_SEMICOLON",
                                 "Statements terminations use 1 semicolon\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/(\s*;\s*){2,}$/;/g;
                        }
                }

# check for #defines like: 1 << <digit> that could be BIT(digit), it is not exported to uapi
                if ($realfile !~ m@^include/uapi/@ &&
                    $line =~ /#\s*define\s+\w+\s+\(?\s*1\s*([ulUL]*)\s*\<\<\s*(?:\d+|$Ident)\s*\)?/) {
                        my $ull = "";
                        $ull = "_ULL" if (defined($1) && $1 =~ /ll/i);
                        if (CHK("BIT_MACRO",
                                "Prefer using the BIT$ull macro\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\(?\s*1\s*[ulUL]*\s*<<\s*(\d+|$Ident)\s*\)?/BIT${ull}($1)/;
                        }
                }

# check for #if defined CONFIG_<FOO> || defined CONFIG_<FOO>_MODULE
                if ($line =~ /^\+\s*#\s*if\s+defined(?:\s*\(?\s*|\s+)(CONFIG_[A-Z_]+)\s*\)?\s*\|\|\s*defined(?:\s*\(?\s*|\s+)\1_MODULE\s*\)?\s*$/) {
                        my $config = $1;
                        if (WARN("PREFER_IS_ENABLED",
                                 "Prefer IS_ENABLED(<FOO>) to CONFIG_<FOO> || CONFIG_<FOO>_MODULE\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] = "\+#if IS_ENABLED($config)";
                        }
                }

# check for case / default statements not preceded by break/fallthrough/switch
                if ($line =~ /^.\s*(?:case\s+(?:$Ident|$Constant)\s*|default):/) {
                        my $has_break = 0;
                        my $has_statement = 0;
                        my $count = 0;
                        my $prevline = $linenr;
                        while ($prevline > 1 && ($file || $count < 3) && !$has_break) {
                                $prevline--;
                                my $rline = $rawlines[$prevline - 1];
                                my $fline = $lines[$prevline - 1];
                                last if ($fline =~ /^\@\@/);
                                next if ($fline =~ /^\-/);
                                next if ($fline =~ /^.(?:\s*(?:case\s+(?:$Ident|$Constant)[\s$;]*|default):[\s$;]*)*$/);
                                $has_break = 1 if ($rline =~ /fall[\s_-]*(through|thru)/i);
                                next if ($fline =~ /^.[\s$;]*$/);
                                $has_statement = 1;
                                $count++;
                                $has_break = 1 if ($fline =~ /\bswitch\b|\b(?:break\s*;[\s$;]*$|exit\s*\(\b|return\b|goto\b|continue\b)/);
                        }
                        if (!$has_break && $has_statement) {
                                WARN("MISSING_BREAK",
                                     "Possible switch case/default not preceded by break or fallthrough comment\n" . $herecurr);
                        }
                }

# check for switch/default statements without a break;
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /^\+[$;\s]*(?:case[$;\s]+\w+[$;\s]*:[$;\s]*|)*[$;\s]*\bdefault[$;\s]*:[$;\s]*;/g) {
                        my $cnt = statement_rawlines($stat);
                        my $herectx = get_stat_here($linenr, $cnt, $here);

                        WARN("DEFAULT_NO_BREAK",
                             "switch default: should use break\n" . $herectx);
                }

# check for gcc specific __FUNCTION__
                if ($line =~ /\b__FUNCTION__\b/) {
                        if (WARN("USE_FUNC",
                                 "__func__ should be used instead of gcc specific __FUNCTION__\n"  . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\b__FUNCTION__\b/__func__/g;
                        }
                }

# check for uses of __DATE__, __TIME__, __TIMESTAMP__
                while ($line =~ /\b(__(?:DATE|TIME|TIMESTAMP)__)\b/g) {
                        ERROR("DATE_TIME",
                              "Use of the '$1' macro makes the build non-deterministic\n" . $herecurr);
                }

# check for use of yield()
                if ($line =~ /\byield\s*\(\s*\)/) {
                        WARN("YIELD",
                             "Using yield() is generally wrong. See yield() kernel-doc (sched/core.c)\n"  . $herecurr);
                }

# check for comparisons against true and false
                if ($line =~ /\+\s*(.*?)\b(true|false|$Lval)\s*(==|\!=)\s*(true|false|$Lval)\b(.*)$/i) {
                        my $lead = $1;
                        my $arg = $2;
                        my $test = $3;
                        my $otype = $4;
                        my $trail = $5;
                        my $op = "!";

                        ($arg, $otype) = ($otype, $arg) if ($arg =~ /^(?:true|false)$/i);

                        my $type = lc($otype);
                        if ($type =~ /^(?:true|false)$/) {
                                if (("$test" eq "==" && "$type" eq "true") ||
                                    ("$test" eq "!=" && "$type" eq "false")) {
                                        $op = "";
                                }

                                CHK("BOOL_COMPARISON",
                                    "Using comparison to $otype is error prone\n" . $herecurr);

## maybe suggesting a correct construct would better
##                                  "Using comparison to $otype is error prone.  Perhaps use '${lead}${op}${arg}${trail}'\n" . $herecurr);

                        }
                }

# check for bool bitfields
                if ($sline =~ /^.\s+bool\s*$Ident\s*:\s*\d+\s*;/) {
                        WARN("BOOL_BITFIELD",
                             "Avoid using bool as bitfield.  Prefer bool bitfields as unsigned int or u<8|16|32>\n" . $herecurr);
                }

# check for semaphores initialized locked
                if ($line =~ /^.\s*sema_init.+,\W?0\W?\)/) {
                        WARN("CONSIDER_COMPLETION",
                             "consider using a completion\n" . $herecurr);
                }

# recommend kstrto* over simple_strto* and strict_strto*
                if ($line =~ /\b((simple|strict)_(strto(l|ll|ul|ull)))\s*\(/) {
                        WARN("CONSIDER_KSTRTO",
                             "$1 is obsolete, use k$3 instead\n" . $herecurr);
                }

# check for __initcall(), use device_initcall() explicitly or more appropriate function please
                if ($line =~ /^.\s*__initcall\s*\(/) {
                        WARN("USE_DEVICE_INITCALL",
                             "please use device_initcall() or more appropriate function instead of __initcall() (see include/linux/init.h)\n" . $herecurr);
                }

# check for various structs that are normally const (ops, kgdb, device_tree)
# and avoid what seem like struct definitions 'struct foo {'
                if ($line !~ /\bconst\b/ &&
                    $line =~ /\bstruct\s+($const_structs)\b(?!\s*\{)/) {
                        WARN("CONST_STRUCT",
                             "struct $1 should normally be const\n" . $herecurr);
                }

# use of NR_CPUS is usually wrong
# ignore definitions of NR_CPUS and usage to define arrays as likely right
                if ($line =~ /\bNR_CPUS\b/ &&
                    $line !~ /^.\s*\s*#\s*if\b.*\bNR_CPUS\b/ &&
                    $line !~ /^.\s*\s*#\s*define\b.*\bNR_CPUS\b/ &&
                    $line !~ /^.\s*$Declare\s.*\[[^\]]*NR_CPUS[^\]]*\]/ &&
                    $line !~ /\[[^\]]*\.\.\.[^\]]*NR_CPUS[^\]]*\]/ &&
                    $line !~ /\[[^\]]*NR_CPUS[^\]]*\.\.\.[^\]]*\]/)
                {
                        WARN("NR_CPUS",
                             "usage of NR_CPUS is often wrong - consider using cpu_possible(), num_possible_cpus(), for_each_possible_cpu(), etc\n" . $herecurr);
                }

# Use of __ARCH_HAS_<FOO> or ARCH_HAVE_<BAR> is wrong.
                if ($line =~ /\+\s*#\s*define\s+((?:__)?ARCH_(?:HAS|HAVE)\w*)\b/) {
                        ERROR("DEFINE_ARCH_HAS",
                              "#define of '$1' is wrong - use Kconfig variables or standard guards instead\n" . $herecurr);
                }

# likely/unlikely comparisons similar to "(likely(foo) > 0)"
                if ($^V && $^V ge 5.10.0 &&
                    $line =~ /\b((?:un)?likely)\s*\(\s*$FuncArg\s*\)\s*$Compare/) {
                        WARN("LIKELY_MISUSE",
                             "Using $1 should generally have parentheses around the comparison\n" . $herecurr);
                }

# whine mightly about in_atomic
                if ($line =~ /\bin_atomic\s*\(/) {
                        if ($realfile =~ m@^drivers/@) {
                                ERROR("IN_ATOMIC",
                                      "do not use in_atomic in drivers\n" . $herecurr);
                        } elsif ($realfile !~ m@^kernel/@) {
                                WARN("IN_ATOMIC",
                                     "use of in_atomic() is incorrect outside core kernel code\n" . $herecurr);
                        }
                }

# check for mutex_trylock_recursive usage
                if ($line =~ /mutex_trylock_recursive/) {
                        ERROR("LOCKING",
                              "recursive locking is bad, do not use this ever.\n" . $herecurr);
                }

# check for lockdep_set_novalidate_class
                if ($line =~ /^.\s*lockdep_set_novalidate_class\s*\(/ ||
                    $line =~ /__lockdep_no_validate__\s*\)/ ) {
                        if ($realfile !~ m@^kernel/lockdep@ &&
                            $realfile !~ m@^include/linux/lockdep@ &&
                            $realfile !~ m@^drivers/base/core@) {
                                ERROR("LOCKDEP",
                                      "lockdep_no_validate class is reserved for device->mutex.\n" . $herecurr);
                        }
                }

                if ($line =~ /debugfs_create_\w+.*\b$mode_perms_world_writable\b/ ||
                    $line =~ /DEVICE_ATTR.*\b$mode_perms_world_writable\b/) {
                        WARN("EXPORTED_WORLD_WRITABLE",
                             "Exporting world writable files is usually an error. Consider more restrictive permissions.\n" . $herecurr);
                }

# check for DEVICE_ATTR uses that could be DEVICE_ATTR_<FOO>
# and whether or not function naming is typical and if
# DEVICE_ATTR permissions uses are unusual too
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $stat =~ /\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?\s*(\s*(?:${multi_mode_perms_string_search}|0[0-7]{3,3})\s*)\s*\)?\s*,\s*(\w+)\s*,\s*(\w+)\s*\)/) {
                        my $var = $1;
                        my $perms = $2;
                        my $show = $3;
                        my $store = $4;
                        my $octal_perms = perms_to_octal($perms);
                        if ($show =~ /^${var}_show$/ &&
                            $store =~ /^${var}_store$/ &&
                            $octal_perms eq "0644") {
                                if (WARN("DEVICE_ATTR_RW",
                                         "Use DEVICE_ATTR_RW\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\bDEVICE_ATTR\s*\(\s*$var\s*,\s*\Q$perms\E\s*,\s*$show\s*,\s*$store\s*\)/DEVICE_ATTR_RW(${var})/;
                                }
                        } elsif ($show =~ /^${var}_show$/ &&
                                 $store =~ /^NULL$/ &&
                                 $octal_perms eq "0444") {
                                if (WARN("DEVICE_ATTR_RO",
                                         "Use DEVICE_ATTR_RO\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\bDEVICE_ATTR\s*\(\s*$var\s*,\s*\Q$perms\E\s*,\s*$show\s*,\s*NULL\s*\)/DEVICE_ATTR_RO(${var})/;
                                }
                        } elsif ($show =~ /^NULL$/ &&
                                 $store =~ /^${var}_store$/ &&
                                 $octal_perms eq "0200") {
                                if (WARN("DEVICE_ATTR_WO",
                                         "Use DEVICE_ATTR_WO\n" . $herecurr) &&
                                    $fix) {
                                        $fixed[$fixlinenr] =~ s/\bDEVICE_ATTR\s*\(\s*$var\s*,\s*\Q$perms\E\s*,\s*NULL\s*,\s*$store\s*\)/DEVICE_ATTR_WO(${var})/;
                                }
                        } elsif ($octal_perms eq "0644" ||
                                 $octal_perms eq "0444" ||
                                 $octal_perms eq "0200") {
                                my $newshow = "$show";
                                $newshow = "${var}_show" if ($show ne "NULL" && $show ne "${var}_show");
                                my $newstore = $store;
                                $newstore = "${var}_store" if ($store ne "NULL" && $store ne "${var}_store");
                                my $rename = "";
                                if ($show ne $newshow) {
                                        $rename .= " '$show' to '$newshow'";
                                }
                                if ($store ne $newstore) {
                                        $rename .= " '$store' to '$newstore'";
                                }
                                WARN("DEVICE_ATTR_FUNCTIONS",
                                     "Consider renaming function(s)$rename\n" . $herecurr);
                        } else {
                                WARN("DEVICE_ATTR_PERMS",
                                     "DEVICE_ATTR unusual permissions '$perms' used\n" . $herecurr);
                        }
                }

# Mode permission misuses where it seems decimal should be octal
# This uses a shortcut match to avoid unnecessary uses of a slow foreach loop
# o Ignore module_param*(...) uses with a decimal 0 permission as that has a
#   specific definition of not visible in sysfs.
# o Ignore proc_create*(...) uses with a decimal 0 permission as that means
#   use the default permissions
                if ($^V && $^V ge 5.10.0 &&
                    defined $stat &&
                    $line =~ /$mode_perms_search/) {
                        foreach my $entry (@mode_permission_funcs) {
                                my $func = $entry->[0];
                                my $arg_pos = $entry->[1];

                                my $lc = $stat =~ tr@\n@@;
                                $lc = $lc + $linenr;
                                my $stat_real = get_stat_real($linenr, $lc);

                                my $skip_args = "";
                                if ($arg_pos > 1) {
                                        $arg_pos--;
                                        $skip_args = "(?:\\s*$FuncArg\\s*,\\s*){$arg_pos,$arg_pos}";
                                }
                                my $test = "\\b$func\\s*\\(${skip_args}($FuncArg(?:\\|\\s*$FuncArg)*)\\s*[,\\)]";
                                if ($stat =~ /$test/) {
                                        my $val = $1;
                                        $val = $6 if ($skip_args ne "");
                                        if (!($func =~ /^(?:module_param|proc_create)/ && $val eq "0") &&
                                            (($val =~ /^$Int$/ && $val !~ /^$Octal$/) ||
                                             ($val =~ /^$Octal$/ && length($val) ne 4))) {
                                                ERROR("NON_OCTAL_PERMISSIONS",
                                                      "Use 4 digit octal (0777) not decimal permissions\n" . "$here\n" . $stat_real);
                                        }
                                        if ($val =~ /^$Octal$/ && (oct($val) & 02)) {
                                                ERROR("EXPORTED_WORLD_WRITABLE",
                                                      "Exporting writable files is usually an error. Consider more restrictive permissions.\n" . "$here\n" . $stat_real);
                                        }
                                }
                        }
                }

# check for uses of S_<PERMS> that could be octal for readability
                while ($line =~ m{\b($multi_mode_perms_string_search)\b}g) {
                        my $oval = $1;
                        my $octal = perms_to_octal($oval);
                        if (WARN("SYMBOLIC_PERMS",
                                 "Symbolic permissions '$oval' are not preferred. Consider using octal permissions '$octal'.\n" . $herecurr) &&
                            $fix) {
                                $fixed[$fixlinenr] =~ s/\Q$oval\E/$octal/;
                        }
                }

# validate content of MODULE_LICENSE against list from include/linux/module.h
                if ($line =~ /\bMODULE_LICENSE\s*\(\s*($String)\s*\)/) {
                        my $extracted_string = get_quoted_string($line, $rawline);
                        my $valid_licenses = qr{
                                                GPL|
                                                GPL\ v2|
                                                GPL\ and\ additional\ rights|
                                                Dual\ BSD/GPL|
                                                Dual\ MIT/GPL|
                                                Dual\ MPL/GPL|
                                                Proprietary
                                        }x;
                        if ($extracted_string !~ /^"(?:$valid_licenses)"$/x) {
                                WARN("MODULE_LICENSE",
                                     "unknown module license " . $extracted_string . "\n" . $herecurr);
                        }
                }
        }

        # If we have no input at all, then there is nothing to report on
        # so just keep quiet.
        if ($#rawlines == -1) {
                exit(0);
        }

        # In mailback mode only produce a report in the negative, for
        # things that appear to be patches.
        if ($mailback && ($clean == 1 || !$is_patch)) {
                exit(0);
        }

        # This is not a patch, and we are are in 'no-patch' mode so
        # just keep quiet.
        if (!$chk_patch && !$is_patch) {
                exit(0);
        }

        if (!$is_patch && $filename !~ /cover-letter\.patch$/) {
                ERROR("NOT_UNIFIED_DIFF",
                      "Does not appear to be a unified-diff format patch\n");
        }
        if ($is_patch && $has_commit_log && $chk_signoff && $signoff == 0) {
                ERROR("MISSING_SIGN_OFF",
                      "Missing Signed-off-by: line(s)\n");
        }

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

        if ($quiet == 0) {
                # If there were any defects found and not already fixing them
                if (!$clean and !$fix) {
                        print << "EOM"

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.
EOM
                }
                # If there were whitespace errors which cleanpatch can fix
                # then suggest that.
                if ($rpt_cleaners) {
                        $rpt_cleaners = 0;
                        print << "EOM"

NOTE: Whitespace errors detected.
      You may wish to use scripts/cleanpatch or scripts/cleanfile
EOM
                }
        }

        if ($clean == 0 && $fix &&
            ("@rawlines" ne "@fixed" ||
             $#fixed_inserted >= 0 || $#fixed_deleted >= 0)) {
                my $newfile = $filename;
                $newfile .= ".EXPERIMENTAL-checkpatch-fixes" if (!$fix_inplace);
                my $linecount = 0;
                my $f;

                @fixed = fix_inserted_deleted_lines(\@fixed, \@fixed_inserted, \@fixed_deleted);

                open($f, '>', $newfile)
                    or die "$P: Can't open $newfile for write\n";
                foreach my $fixed_line (@fixed) {
                        $linecount++;
                        if ($file) {
                                if ($linecount > 3) {
                                        $fixed_line =~ s/^\+//;
                                        print $f $fixed_line . "\n";
                                }
                        } else {
                                print $f $fixed_line . "\n";
                        }
                }
                close($f);

                if (!$quiet) {
                        print << "EOM";

Wrote EXPERIMENTAL --fix correction(s) to '$newfile'

Do _NOT_ trust the results written to this file.
Do _NOT_ submit these changes without inspecting them for correctness.

This EXPERIMENTAL file is simply a convenience to help rewrite patches.
No warranties, expressed or implied...
EOM
                }
        }

        if ($quiet == 0) {
                print "\n";
                if ($clean == 1) {
                        print "$vname has no obvious style problems and is ready for submission.\n";
                } else {
                        print "$vname has style problems, please review.\n";
                }
        }
        return $clean;
}