RT-AC66 3.0.0.4.374.130 core

[tomato.git] / release / src-rt-6.x / linux / linux-2.6 / scripts / checkpatch.pl

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

use strict;

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

my $V = '0.06';

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

my $quiet = 0;
my $tree = 1;
my $chk_signoff = 1;
my $chk_patch = 1;
my $tst_type = 0;
GetOptions(
        'q|quiet'       => \$quiet,
        'tree!'         => \$tree,
        'signoff!'      => \$chk_signoff,
        'patch!'        => \$chk_patch,
        'test-type!'    => \$tst_type,
) or exit;

my $exit = 0;

if ($#ARGV < 0) {
        print "usage: $P [options] patchfile\n";
        print "version: $V\n";
        print "options: -q           => quiet\n";
        print "         --no-tree    => run without a kernel tree\n";
        exit(1);
}

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

my @dep_includes = ();
my @dep_functions = ();
my $removal = 'Documentation/feature-removal-schedule.txt';
if ($tree && -f $removal) {
        open(REMOVE, "<$removal") || die "$P: $removal: open failed - $!\n";
        while (<REMOVE>) {
                if (/^Files:\s+(.*\S)/) {
                        for my $file (split(/[, ]+/, $1)) {
                                if ($file =~ m@include/(.*)@) {
                                        push(@dep_includes, $1);
                                }
                        }

                } elsif (/^Funcs:\s+(.*\S)/) {
                        for my $func (split(/[, ]+/, $1)) {
                                push(@dep_functions, $func);
                        }
                }
        }
}

my @rawlines = ();
while (<>) {
        chomp;
        push(@rawlines, $_);
        if (eof(ARGV)) {
                if (!process($ARGV, @rawlines)) {
                        $exit = 1;
                }
                @rawlines = ();
        }
}

exit($exit);

sub top_of_kernel_tree {
        if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
            (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
            (-d "Documentation") && (-d "arch") && (-d "include") &&
            (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
            (-d "kernel") && (-d "lib") && (-d "scripts")) {
                return 1;
        }
        return 0;
}

sub expand_tabs {
        my ($str) = @_;

        my $res = '';
        my $n = 0;
        for my $c (split(//, $str)) {
                if ($c eq "\t") {
                        $res .= ' ';
                        $n++;
                        for (; ($n % 8) != 0; $n++) {
                                $res .= ' ';
                        }
                        next;
                }
                $res .= $c;
                $n++;
        }

        return $res;
}

sub 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));
}

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

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

        my $quote = '';

        foreach my $c (split(//, $line)) {
                if ($l ne "\\" && ($c eq "'" || $c eq '"')) {
                        if ($quote eq '') {
                                $quote = $c;
                                $res .= $c;
                                $l = $c;
                                next;
                        } elsif ($quote eq $c) {
                                $quote = '';
                        }
                }
                if ($quote && $c ne "\t") {
                        $res .= "X";
                } else {
                        $res .= $c;
                }

                $l = $c;
        }

        return $res;
}

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

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

                $blk .= $rawlines[$line];

                @o = ($blk =~ /$open/g);
                @c = ($blk =~ /$close/g);

                if (!$outer || (scalar(@o) - scalar(@c)) == 1) {
                        push(@res, $rawlines[$line]);
                }

                last if (scalar(@o) == scalar(@c));
        }

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

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

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

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

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

        # Catch a comment on the end of the line itself.
        my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*$@);
        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 cat_vet {
        my ($vet) = @_;

        $vet =~ s/\t/^I/;
        $vet =~ s/$/\$/;

        return $vet;
}

sub process {
        my $filename = shift;
        my @lines = @_;

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

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

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

        # Trace the real file/line as we go.
        my $realfile = '';
        my $realline = 0;
        my $realcnt = 0;
        my $here = '';
        my $in_comment = 0;
        my $first_line = 0;

        my $Ident       = qr{[A-Za-z\d_]+};
        my $Storage     = qr{extern|static};
        my $Sparse      = qr{__user|__kernel|__force|__iomem};
        my $NonptrType  = qr{
                                \b
                                (?:const\s+)?
                                (?:unsigned\s+)?
                                (?:
                                        void|
                                        char|
                                        short|
                                        int|
                                        long|
                                        unsigned|
                                        float|
                                        double|
                                        long\s+int|
                                        long\s+long|
                                        long\s+long\s+int|
                                        struct\s+$Ident|
                                        union\s+$Ident|
                                        ${Ident}_t
                                )
                                (?:\s+$Sparse)*
                                \b
                          }x;
        my $Type        = qr{
                                \b$NonptrType\b
                                (?:\s*\*+\s*const|\s*\*+)?
                          }x;
        my $Declare     = qr{(?:$Storage\s+)?$Type};
        my $Attribute   = qr{__read_mostly|__init|__initdata};

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

                my $rawline = $line;

#extract the filename as it passes
                if ($line=~/^\+\+\+\s+(\S+)/) {
                        $realfile=$1;
                        $realfile =~ s@^[^/]*/@@;
                        $in_comment = 0;
                        next;
                }
#extract the line range in the file after the patch is applied
                if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
                        $is_patch = 1;
                        $first_line = $linenr + 1;
                        $in_comment = 0;
                        $realline=$1-1;
                        if (defined $2) {
                                $realcnt=$3+1;
                        } else {
                                $realcnt=1+1;
                        }
                        next;
                }

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

                        # track any sort of multi-line comment.  Obviously if
                        # the added text or context do not include the whole
                        # comment we will not see it. Such is life.
                        #
                        # Guestimate if this is a continuing comment.  If this
                        # is the start of a diff block and this line starts
                        # ' *' then it is very likely a comment.
                        if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
                                $in_comment = 1;
                        }
                        if ($line =~ m@/\*@) {
                                $in_comment = 1;
                        }
                        if ($line =~ m@\*/@) {
                                $in_comment = 0;
                        }

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

                        # Track the previous line.
                        ($prevline, $stashline) = ($stashline, $line);
                        ($previndent, $stashindent) = ($stashindent, $indent);
                } elsif ($realcnt == 1) {
                        $realcnt--;
                }

#make up the handle for any error we report on this line
                $here = "#$linenr: ";
                $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);

                my $hereline = "$here\n$line\n";
                my $herecurr = "$here\n$line\n\n";
                my $hereprev = "$here\n$prevline\n$line\n\n";

#check the patch for a signoff:
                if ($line =~ /^\s*signed-off-by:/i) {
                        # This is a signoff, if ugly, so do not double report.
                        $signoff++;
                        if (!($line =~ /^\s*Signed-off-by:/)) {
                                print "Signed-off-by: is the preferred form\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                        if ($line =~ /^\s*signed-off-by:\S/i) {
                                print "need space after Signed-off-by:\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                }

# Check for wrappage within a valid hunk of the file
                if ($realcnt != 0 && $line !~ m{^(?:\+|-| |$)}) {
                        print "patch seems to be corrupt (line wrapped?) [$realcnt]\n";
                        print "$herecurr";
                        $clean = 0;
                }

#ignore lines being removed
                if ($line=~/^-/) {next;}

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

#trailing whitespace
                if ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
                        my $herevet = "$here\n" . cat_vet($line) . "\n\n";
                        print "trailing whitespace\n";
                        print "$herevet";
                        $clean = 0;
                }
#80 column limit
                if ($line =~ /^\+/ && !($prevline=~/\/\*\*/) && $length > 80) {
                        print "line over 80 characters\n";
                        print "$herecurr";
                        $clean = 0;
                }

# check we are in a valid source file *.[hc] if not then ignore this hunk
                next if ($realfile !~ /\.[hc]$/);

# at the beginning of a line any tabs must come first and anything
# more than 8 must use tabs.
                if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
                        my $herevet = "$here\n" . cat_vet($line) . "\n\n";
                        print "use tabs not spaces\n";
                        print "$herevet";
                        $clean = 0;
                }

                #
                # The rest of our checks refer specifically to C style
                # only apply those _outside_ comments.
                #
                next if ($in_comment);

# Remove comments from the line before processing.
                $line =~ s@/\*.*\*/@@g;
                $line =~ s@/\*.*@@;
                $line =~ s@.*\*/@@;

# Standardise the strings and chars within the input to simplify matching.
                $line = sanitise_line($line);

#
# 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 '') {
                                print "switch and case should be at the same indent\n";
                                print "$here\n$line\n$err\n";
                                $clean = 0;
                        }
                }

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

# TEST: allow direct testing of the type matcher.
                if ($tst_type && $line =~ /^.$Declare$/) {
                        print "TEST: is type $Declare\n";
                        print "$herecurr";
                        $clean = 0;
                        next;
                }

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

# check for malformed paths in #include statements (uses RAW line)
                if ($rawline =~ m{^.#\s*include\s+[<"](.*)[">]}) {
                        my $path = $1;
                        if ($path =~ m{//}) {
                                print "malformed #include filename\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                        # Sanitise this special form of string.
                        $path = 'X' x length($path);
                        $line =~ s{\<.*\>}{<$path>};
                }

# no C99 // comments
                if ($line =~ m{//}) {
                        print "do not use C99 // comments\n";
                        print "$herecurr";
                        $clean = 0;
                }
                # Remove C99 comments.
                $line =~ s@//.*@@;

#EXPORT_SYMBOL should immediately follow its function closing }.
                if (($line =~ /EXPORT_SYMBOL.*\((.*)\)/) ||
                    ($line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
                        my $name = $1;
                        if (($prevline !~ /^}/) &&
                           ($prevline !~ /^\+}/) &&
                           ($prevline !~ /^ }/) &&
                           ($prevline !~ /\s$name(?:\s+$Attribute)?\s*(?:;|=)/)) {
                                print "EXPORT_SYMBOL(foo); should immediately follow its function/variable\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                }

# check for static initialisers.
                if ($line=~/\s*static\s.*=\s+(0|NULL);/) {
                        print "do not initialise statics to 0 or NULL\n";
                        print "$herecurr";
                        $clean = 0;
                }

# check for new typedefs, only function parameters and sparse annotations
# make sense.
                if ($line =~ /\btypedef\s/ &&
                    $line !~ /\btypedef\s+$Type\s+\(\s*$Ident\s*\)\s*\(/ &&
                    $line !~ /\b__bitwise(?:__|)\b/) {
                        print "do not add new typedefs\n";
                        print "$herecurr";
                        $clean = 0;
                }

# * goes on variable not on type
                if ($line =~ m{\($NonptrType(\*+)(?:\s+const)?\)}) {
                        print "\"(foo$1)\" should be \"(foo $1)\"\n";
                        print "$herecurr";
                        $clean = 0;

                } elsif ($line =~ m{\($NonptrType\s+(\*+)(?!\s+const)\s+\)}) {
                        print "\"(foo $1 )\" should be \"(foo $1)\"\n";
                        print "$herecurr";
                        $clean = 0;

                } elsif ($line =~ m{$NonptrType(\*+)(?:\s+const)?\s+[A-Za-z\d_]+}) {
                        print "\"foo$1 bar\" should be \"foo $1bar\"\n";
                        print "$herecurr";
                        $clean = 0;

                } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+const)\s+[A-Za-z\d_]+}) {
                        print "\"foo $1 bar\" should be \"foo $1bar\"\n";
                        print "$herecurr";
                        $clean = 0;
                }

# # no BUG() or BUG_ON()
#               if ($line =~ /\b(BUG|BUG_ON)\b/) {
#                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
#                       print "$herecurr";
#                       $clean = 0;
#               }

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

# function brace can't be on same line, except for #defines of do while,
# or if closed on same line
                if (($line=~/$Type\s*[A-Za-z\d_]+\(.*\).* {/) and
                    !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
                        print "braces following function declarations go on the next line\n";
                        print "$herecurr";
                        $clean = 0;
                }

# Check operator spacing.
                # Note we expand the line with the leading + as the real
                # line will be displayed with the leading + and the tabs
                # will therefore also expand that way.
                my $opline = $line;
                $opline = expand_tabs($opline);
                $opline =~ s/^./ /;
                if (!($line=~/\#\s*include/)) {
                        my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
                        my $off = 0;
                        for (my $n = 0; $n < $#elements; $n += 2) {
                                $off += length($elements[$n]);

                                my $a = '';
                                $a = 'V' if ($elements[$n] ne '');
                                $a = 'W' if ($elements[$n] =~ /\s$/);
                                $a = 'B' if ($elements[$n] =~ /(\[|\()$/);
                                $a = 'O' if ($elements[$n] eq '');
                                $a = 'E' if ($elements[$n] eq '' && $n == 0);

                                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/);
                                        $c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
                                        $c = 'O' if ($elements[$n + 2] eq '');
                                } else {
                                        $c = 'E';
                                }

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

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

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

                                my $ptr = (" " x $off) . "^";
                                my $hereptr = "$hereline$ptr\n\n";

                                ##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";

                                # ; should have either the end of line or a space or \ after it
                                if ($op eq ';') {
                                        if ($ctx !~ /.x[WE]/ && $cc !~ /^\\/) {
                                                print "need space after that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

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

                                # -> should have no spaces
                                } elsif ($op eq '->') {
                                        if ($ctx =~ /Wx.|.xW/) {
                                                print "no spaces around that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # , must have a space on the right.
                                } elsif ($op eq ',') {
                                        if ($ctx !~ /.xW|.xE/ && $cc !~ /^}/) {
                                                print "need space after that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # unary ! and unary ~ are allowed no space on the right
                                } elsif ($op eq '!' or $op eq '~') {
                                        if ($ctx !~ /[WOEB]x./) {
                                                print "need space before that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }
                                        if ($ctx =~ /.xW/) {
                                                print "no space after that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # unary ++ and unary -- are allowed no space on one side.
                                } elsif ($op eq '++' or $op eq '--') {
                                        if ($ctx !~ /[WOB]x[^W]/ && $ctx !~ /[^W]x[WOBE]/) {
                                                print "need space one side of that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }
                                        if ($ctx =~ /Wx./ && $cc =~ /^;/) {
                                                print "no space before that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # & is both unary and binary
                                # unary:
                                #       a &b
                                # binary (consistent spacing):
                                #       a&b             OK
                                #       a & b           OK
                                #
                                # boiling down to: if there is a space on the right then there
                                # should be one on the left.
                                #
                                # - is the same
                                #
                                } elsif ($op eq '&' or $op eq '-') {
                                        if ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]/) {
                                                print "need space before that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # * is the same as & only adding:
                                # type:
                                #       (foo *)
                                #       (foo **)
                                #
                                } elsif ($op eq '*') {
                                        if ($ca eq '*') {
                                                if ($cc =~ /^\s(?!\s*const)/) {
                                                        print "no space after that '$op' $at\n";
                                                        print "$hereptr";
                                                        $clean = 0;
                                                }
                                        } elsif ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]|OxV|WxB|BxB/) {
                                                print "need space before that '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # << and >> may either have or not have spaces both sides
                                } elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
                                         $op eq '^' or $op eq '|')
                                {
                                        if ($ctx !~ /VxV|WxW|VxE|WxE/) {
                                                print "need consistent spacing around '$op' $at\n";
                                                print "$hereptr";
                                                $clean = 0;
                                        }

                                # All the others need spaces both sides.
                                } elsif ($ctx !~ /[EW]x[WE]/) {
                                        print "need spaces around that '$op' $at\n";
                                        print "$hereptr";
                                        $clean = 0;
                                }
                                $off += length($elements[$n + 1]);
                        }
                }

#need space before brace following if, while, etc
                if ($line=~/\(.*\){/) {
                        print "need a space before the brace\n";
                        print "$herecurr";
                        $clean = 0;
                }

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

# Need a space before open parenthesis after if, while etc
                if ($line=~/\b(if|while|for|switch)\(/) {
                        print "need a space before the open parenthesis\n";
                        print "$herecurr";
                        $clean = 0;
                }

# Check for illegal assignment in if conditional.
                if ($line=~/\bif\s*\(.*[^<>!=]=[^=].*\)/) {
                        #next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
                        print "do not use assignment in if condition\n";
                        print "$herecurr";
                        $clean = 0;
                }

                # Check for }<nl>else {, these must be at the same
                # indent level to be relevant to each other.
                if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
                                                $previndent == $indent) {
                        print "else should follow close brace\n";
                        print "$hereprev";
                        $clean = 0;
                }

#studly caps, commented out until figure out how to distinguish between use of existing and adding new
#               if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
#                   print "No studly caps, use _\n";
#                   print "$herecurr";
#                   $clean = 0;
#               }

#no spaces allowed after \ in define
                if ($line=~/\#define.*\\\s$/) {
                        print("Whitepspace after \\ makes next lines useless\n");
                        print "$herecurr";
                        $clean = 0;
                }

#warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
                if ($tree && $rawline =~ m{^.\#\s*include\s*\<asm\/(.*)\.h\>}) {
                        my $checkfile = "include/linux/$1.h";
                        if (-f $checkfile) {
                                print "Use #include <linux/$1.h> instead of <asm/$1.h>\n";
                                print $herecurr;
                                $clean = 0;
                        }
                }

# if/while/etc brace do not go on next line, unless defining a do while loop,
# or if that brace on the next line is for something else
                if ($prevline=~/\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/) {
                        my @opened = $prevline=~/\(/g;
                        my @closed = $prevline=~/\)/g;
                        my $nr_line = $linenr;
                        my $remaining = $realcnt - 1;
                        my $next_line = $line;
                        my $extra_lines = 0;
                        my $display_segment = $prevline;

                        while ($remaining > 0 && scalar @opened > scalar @closed) {
                                $prevline .= $next_line;
                                $display_segment .= "\n" . $next_line;
                                $next_line = $lines[$nr_line];
                                $nr_line++;
                                $remaining--;

                                @opened = $prevline=~/\(/g;
                                @closed = $prevline=~/\)/g;
                        }

                        if (($prevline=~/\b(?:(if|while|for|switch)\s*\(.*\)|do|else)\s*$/) and ($next_line=~/{/) and
                           !($next_line=~/\b(?:if|while|for|switch|do|else)\b/) and !($next_line=~/\#define.*do.*while/)) {
                                print "That { should be on the previous line\n";
                                print "$here\n$display_segment\n$next_line\n\n";
                                $clean = 0;
                        }
                }

# if and else should not have general statements after it
                if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/ &&
                    $1 !~ /^\s*(?:\sif|{|$)/) {
                        print "trailing statements should be on next line\n";
                        print "$herecurr";
                        $clean = 0;
                }

# 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 goot container
                if (($prevline=~/\#define.*\\/) and
                   !($prevline=~/do\s+{/) and !($prevline=~/\(\{/) and
                   !($line=~/do.*{/) and !($line=~/\(\{/) and
                   !($line=~/^.\s*$Declare\s/)) {
                        # Grab the first statement, if that is the entire macro
                        # its ok.  This may start either on the #define line
                        # or the one below.
                        my $ln = $linenr;
                        my $cnt = $realcnt;

                        # If the macro starts on the define line start there.
                        if ($prevline !~ m{^.#\s*define\s*$Ident(?:\([^\)]*\))?\s*\\\s*$}) {
                                $ln--;
                                $cnt++;
                        }
                        my $ctx = join('', ctx_statement($ln, $cnt));

                        if ($ctx =~ /\\$/) {
                                if ($ctx =~ /;/) {
                                        print "Macros with multiple statements should be enclosed in a do - while loop\n";
                                } else {
                                        print "Macros with complex values should be enclosed in parenthesis\n";
                                }
                                print "$hereprev";
                                $clean = 0;
                        }
                }

# don't include deprecated include files (uses RAW line)
                for my $inc (@dep_includes) {
                        if ($rawline =~ m@\#\s*include\s*\<$inc>@) {
                                print "Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                }

# don't use deprecated functions
                for my $func (@dep_functions) {
                        if ($line =~ /\b$func\b/) {
                                print "Don't use $func(): see Documentation/feature-removal-schedule.txt\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                }

# no volatiles please
                if ($line =~ /\bvolatile\b/ && $line !~ /\basm\s+volatile\b/) {
                        print "Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n";
                        print "$herecurr";
                        $clean = 0;
                }

# warn about #if 0
                if ($line =~ /^.#\s*if\s+0\b/) {
                        print "#if 0 -- if this code redundant remove it\n";
                        print "$herecurr";
                        $clean = 0;
                }

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

# check for spinlock_t definitions without a comment.
                if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/) {
                        my $which = $1;
                        if (!ctx_has_comment($first_line, $linenr)) {
                                print "$1 definition without comment\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                }
# check for memory barriers without a comment.
                if ($line =~ /\b(mb|rmb|wmb|read_barrier_depends|smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
                        if (!ctx_has_comment($first_line, $linenr)) {
                                print "memory barrier without comment\n";
                                print "$herecurr";
                                $clean = 0;
                        }
                }
# check of hardware specific defines
                if ($line =~ m@^.#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@) {
                        print "architecture specific defines should be avoided\n";
                        print "$herecurr";
                        $clean = 0;
                }

                if ($line =~ /$Type\s+(?:inline|__always_inline)\b/ ||
                    $line =~ /\b(?:inline|always_inline)\s+$Storage/) {
                        print "inline keyword should sit between storage class and type\n";
                        print "$herecurr";
                        $clean = 0;
                }
        }

        if ($chk_patch && !$is_patch) {
                $clean = 0;
                print "Does not appear to be a unified-diff format patch\n";
        }
        if ($is_patch && $chk_signoff && $signoff == 0) {
                $clean = 0;
                print "Missing Signed-off-by: line(s)\n";
        }

        if ($clean == 1 && $quiet == 0) {
                print "Your patch has no obvious style problems and is ready for submission.\n"
        }
        if ($clean == 0 && $quiet == 0) {
                print "Your patch has style problems, please review.  If any of these errors\n";
                print "are false positives report them to the maintainer, see\n";
                print "CHECKPATCH in MAINTAINERS.\n";
        }
        return $clean;
}