scripts/checkpatch.pl

   1 #!/usr/bin/perl -w
   2 # (c) 2001, Dave Jones. <davej@codemonkey.org.uk> (the file handling bit)
   3 # (c) 2005, Joel Schopp <jschopp@austin.ibm.com> (the ugly bit)
   4 # (c) 2007, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite, etc)
   5 # Licensed under the terms of the GNU GPL License version 2
   6
   7 use strict;
   8
   9 my $P = $0;
  10 $P =~ s@.*/@@g;
  11
  12 my $V = '0.10';
  13
  14 use Getopt::Long qw(:config no_auto_abbrev);
  15
  16 my $quiet = 0;
  17 my $tree = 1;
  18 my $chk_signoff = 1;
  19 my $chk_patch = 1;
  20 my $tst_type = 0;
  21 GetOptions(
  22         'q|quiet'       => \$quiet,
  23         'tree!'         => \$tree,
  24         'signoff!'      => \$chk_signoff,
  25         'patch!'        => \$chk_patch,
  26         'test-type!'    => \$tst_type,
  27 ) or exit;
  28
  29 my $exit = 0;
  30
  31 if ($#ARGV < 0) {
  32         print "usage: $P [options] patchfile\n";
  33         print "version: $V\n";
  34         print "options: -q           => quiet\n";
  35         print "         --no-tree    => run without a kernel tree\n";
  36         exit(1);
  37 }
  38
  39 if ($tree && !top_of_kernel_tree()) {
  40         print "Must be run from the top-level dir. of a kernel tree\n";
  41         exit(2);
  42 }
  43
  44 my @dep_includes = ();
  45 my @dep_functions = ();
  46 my $removal = 'Documentation/feature-removal-schedule.txt';
  47 if ($tree && -f $removal) {
  48         open(REMOVE, "<$removal") || die "$P: $removal: open failed - $!\n";
  49         while (<REMOVE>) {
  50                 if (/^Check:\s+(.*\S)/) {
  51                         for my $entry (split(/[, ]+/, $1)) {
  52                                 if ($entry =~ m@include/(.*)@) {
  53                                         push(@dep_includes, $1);
  54
  55                                 } elsif ($entry !~ m@/@) {
  56                                         push(@dep_functions, $entry);
  57                                 }
  58                         }
  59                 }
  60         }
  61 }
  62
  63 my @rawlines = ();
  64 while (<>) {
  65         chomp;
  66         push(@rawlines, $_);
  67         if (eof(ARGV)) {
  68                 if (!process($ARGV, @rawlines)) {
  69                         $exit = 1;
  70                 }
  71                 @rawlines = ();
  72         }
  73 }
  74
  75 exit($exit);
  76
  77 sub top_of_kernel_tree {
  78         if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
  79             (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
  80             (-d "Documentation") && (-d "arch") && (-d "include") &&
  81             (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
  82             (-d "kernel") && (-d "lib") && (-d "scripts")) {
  83                 return 1;
  84         }
  85         return 0;
  86 }
  87
  88 sub expand_tabs {
  89         my ($str) = @_;
  90
  91         my $res = '';
  92         my $n = 0;
  93         for my $c (split(//, $str)) {
  94                 if ($c eq "\t") {
  95                         $res .= ' ';
  96                         $n++;
  97                         for (; ($n % 8) != 0; $n++) {
  98                                 $res .= ' ';
  99                         }
 100                         next;
 101                 }
 102                 $res .= $c;
 103                 $n++;
 104         }
 105
 106         return $res;
 107 }
 108
 109 sub line_stats {
 110         my ($line) = @_;
 111
 112         # Drop the diff line leader and expand tabs
 113         $line =~ s/^.//;
 114         $line = expand_tabs($line);
 115
 116         # Pick the indent from the front of the line.
 117         my ($white) = ($line =~ /^(\s*)/);
 118
 119         return (length($line), length($white));
 120 }
 121
 122 sub sanitise_line {
 123         my ($line) = @_;
 124
 125         my $res = '';
 126         my $l = '';
 127
 128         my $quote = '';
 129
 130         foreach my $c (split(//, $line)) {
 131                 if ($l ne "\\" && ($c eq "'" || $c eq '"')) {
 132                         if ($quote eq '') {
 133                                 $quote = $c;
 134                                 $res .= $c;
 135                                 $l = $c;
 136                                 next;
 137                         } elsif ($quote eq $c) {
 138                                 $quote = '';
 139                         }
 140                 }
 141                 if ($quote && $c ne "\t") {
 142                         $res .= "X";
 143                 } else {
 144                         $res .= $c;
 145                 }
 146
 147                 $l = $c;
 148         }
 149
 150         return $res;
 151 }
 152
 153 sub ctx_block_get {
 154         my ($linenr, $remain, $outer, $open, $close, $off) = @_;
 155         my $line;
 156         my $start = $linenr - 1;
 157         my $blk = '';
 158         my @o;
 159         my @c;
 160         my @res = ();
 161
 162         my $level = 0;
 163         for ($line = $start; $remain > 0; $line++) {
 164                 next if ($rawlines[$line] =~ /^-/);
 165                 $remain--;
 166
 167                 $blk .= $rawlines[$line];
 168                 foreach my $c (split(//, $rawlines[$line])) {
 169                         ##print "C<$c>L<$level><$open$close>O<$off>\n";
 170                         if ($off > 0) {
 171                                 $off--;
 172                                 next;
 173                         }
 174
 175                         if ($c eq $close && $level > 0) {
 176                                 $level--;
 177                                 last if ($level == 0);
 178                         } elsif ($c eq $open) {
 179                                 $level++;
 180                         }
 181                 }
 182
 183                 if (!$outer || $level <= 1) {
 184                         push(@res, $rawlines[$line]);
 185                 }
 186
 187                 last if ($level == 0);
 188         }
 189
 190         return ($level, @res);
 191 }
 192 sub ctx_block_outer {
 193         my ($linenr, $remain) = @_;
 194
 195         my ($level, @r) = ctx_block_get($linenr, $remain, 1, '{', '}', 0);
 196         return @r;
 197 }
 198 sub ctx_block {
 199         my ($linenr, $remain) = @_;
 200
 201         my ($level, @r) = ctx_block_get($linenr, $remain, 0, '{', '}', 0);
 202         return @r;
 203 }
 204 sub ctx_statement {
 205         my ($linenr, $remain, $off) = @_;
 206
 207         my ($level, @r) = ctx_block_get($linenr, $remain, 0, '(', ')', $off);
 208         return @r;
 209 }
 210 sub ctx_block_level {
 211         my ($linenr, $remain) = @_;
 212
 213         return ctx_block_get($linenr, $remain, 0, '{', '}', 0);
 214 }
 215 sub ctx_statement_level {
 216         my ($linenr, $remain, $off) = @_;
 217
 218         return ctx_block_get($linenr, $remain, 0, '(', ')', $off);
 219 }
 220
 221 sub ctx_locate_comment {
 222         my ($first_line, $end_line) = @_;
 223
 224         # Catch a comment on the end of the line itself.
 225         my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*$@);
 226         return $current_comment if (defined $current_comment);
 227
 228         # Look through the context and try and figure out if there is a
 229         # comment.
 230         my $in_comment = 0;
 231         $current_comment = '';
 232         for (my $linenr = $first_line; $linenr < $end_line; $linenr++) {
 233                 my $line = $rawlines[$linenr - 1];
 234                 #warn "           $line\n";
 235                 if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 236                         $in_comment = 1;
 237                 }
 238                 if ($line =~ m@/\*@) {
 239                         $in_comment = 1;
 240                 }
 241                 if (!$in_comment && $current_comment ne '') {
 242                         $current_comment = '';
 243                 }
 244                 $current_comment .= $line . "\n" if ($in_comment);
 245                 if ($line =~ m@\*/@) {
 246                         $in_comment = 0;
 247                 }
 248         }
 249
 250         chomp($current_comment);
 251         return($current_comment);
 252 }
 253 sub ctx_has_comment {
 254         my ($first_line, $end_line) = @_;
 255         my $cmt = ctx_locate_comment($first_line, $end_line);
 256
 257         ##print "LINE: $rawlines[$end_line - 1 ]\n";
 258         ##print "CMMT: $cmt\n";
 259
 260         return ($cmt ne '');
 261 }
 262
 263 sub ctx_expr_before {
 264         my ($line) = @_;
 265
 266         ##print "CHECK<$line>\n";
 267
 268         my $pos = length($line) - 1;
 269         my $count = 0;
 270         my $c;
 271
 272         for (; $pos >= 0; $pos--) {
 273                 $c = substr($line, $pos, 1);
 274                 ##print "CHECK: c<$c> count<$count>\n";
 275                 if ($c eq ')') {
 276                         $count++;
 277                 } elsif ($c eq '(') {
 278                         last if (--$count == 0);
 279                 }
 280         }
 281
 282         ##print "CHECK: result<" . substr($line, 0, $pos) . ">\n";
 283
 284         return substr($line, 0, $pos);
 285 }
 286
 287 sub cat_vet {
 288         my ($vet) = @_;
 289         my ($res, $coded);
 290
 291         $res = '';
 292         while ($vet =~ /([^[:cntrl:]]*)([[:cntrl:]])/g) {
 293                 $coded = sprintf("^%c", unpack('C', $2) + 64);
 294                 $res .= $1 . $coded;
 295         }
 296         $res =~ s/$/\$/;
 297
 298         return $res;
 299 }
 300
 301 my @report = ();
 302 sub report {
 303         push(@report, $_[0]);
 304 }
 305 sub report_dump {
 306         @report;
 307 }
 308 sub ERROR {
 309         report("ERROR: $_[0]\n");
 310         our $clean = 0;
 311 }
 312 sub WARN {
 313         report("WARNING: $_[0]\n");
 314         our $clean = 0;
 315 }
 316 sub CHK {
 317         report("CHECK: $_[0]\n");
 318         our $clean = 0;
 319 }
 320
 321 sub process {
 322         my $filename = shift;
 323         my @lines = @_;
 324
 325         my $linenr=0;
 326         my $prevline="";
 327         my $stashline="";
 328
 329         my $length;
 330         my $indent;
 331         my $previndent=0;
 332         my $stashindent=0;
 333
 334         our $clean = 1;
 335         my $signoff = 0;
 336         my $is_patch = 0;
 337
 338         # Trace the real file/line as we go.
 339         my $realfile = '';
 340         my $realline = 0;
 341         my $realcnt = 0;
 342         my $here = '';
 343         my $in_comment = 0;
 344         my $first_line = 0;
 345
 346         my $Ident       = qr{[A-Za-z\d_]+};
 347         my $Storage     = qr{extern|static|asmlinkage};
 348         my $Sparse      = qr{
 349                                 __user|
 350                                 __kernel|
 351                                 __force|
 352                                 __iomem|
 353                                 __must_check|
 354                                 __init_refok|
 355                                 fastcall
 356                         }x;
 357         my $Inline      = qr{inline|__always_inline|noinline};
 358         my $NonptrType  = qr{
 359                                 \b
 360                                 (?:const\s+)?
 361                                 (?:unsigned\s+)?
 362                                 (?:
 363                                         void|
 364                                         char|
 365                                         short|
 366                                         int|
 367                                         long|
 368                                         unsigned|
 369                                         float|
 370                                         double|
 371                                         bool|
 372                                         long\s+int|
 373                                         long\s+long|
 374                                         long\s+long\s+int|
 375                                         u8|u16|u32|u64|
 376                                         s8|s16|s32|s64|
 377                                         struct\s+$Ident|
 378                                         union\s+$Ident|
 379                                         enum\s+$Ident|
 380                                         ${Ident}_t
 381                                 )
 382                                 (?:\s+$Sparse)*
 383                                 \b
 384                           }x;
 385         my $Type        = qr{
 386                                 \b$NonptrType\b
 387                                 (?:\s*\*+\s*const|\s*\*+|(?:\s*\[\s*\])+)?
 388                                 (?:\s+$Sparse)*
 389                           }x;
 390         my $Declare     = qr{(?:$Storage\s+)?$Type};
 391         my $Attribute   = qr{
 392                                 const|
 393                                 __read_mostly|
 394                                 __(?:mem|cpu|dev|)(?:initdata|init)
 395                           }x;
 396         my $Member      = qr{->$Ident|\.$Ident|\[[^]]*\]};
 397         my $Lval        = qr{$Ident(?:$Member)*};
 398
 399         # Possible bare types.
 400         my @bare = ();
 401         my $Bare = $NonptrType;
 402
 403         # Pre-scan the patch looking for any __setup documentation.
 404         my @setup_docs = ();
 405         my $setup_docs = 0;
 406         foreach my $line (@lines) {
 407                 if ($line=~/^\+\+\+\s+(\S+)/) {
 408                         $setup_docs = 0;
 409                         if ($1 =~ m@Documentation/kernel-parameters.txt$@) {
 410                                 $setup_docs = 1;
 411                         }
 412                         next;
 413                 }
 414
 415                 if ($setup_docs && $line =~ /^\+/) {
 416                         push(@setup_docs, $line);
 417                 }
 418         }
 419
 420         foreach my $line (@lines) {
 421                 $linenr++;
 422
 423                 my $rawline = $line;
 424
 425 #extract the filename as it passes
 426                 if ($line=~/^\+\+\+\s+(\S+)/) {
 427                         $realfile=$1;
 428                         $realfile =~ s@^[^/]*/@@;
 429                         $in_comment = 0;
 430                         next;
 431                 }
 432 #extract the line range in the file after the patch is applied
 433                 if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
 434                         $is_patch = 1;
 435                         $first_line = $linenr + 1;
 436                         $in_comment = 0;
 437                         $realline=$1-1;
 438                         if (defined $2) {
 439                                 $realcnt=$3+1;
 440                         } else {
 441                                 $realcnt=1+1;
 442                         }
 443                         next;
 444                 }
 445
 446 # track the line number as we move through the hunk, note that
 447 # new versions of GNU diff omit the leading space on completely
 448 # blank context lines so we need to count that too.
 449                 if ($line =~ /^( |\+|$)/) {
 450                         $realline++;
 451                         $realcnt-- if ($realcnt != 0);
 452
 453                         # track any sort of multi-line comment.  Obviously if
 454                         # the added text or context do not include the whole
 455                         # comment we will not see it. Such is life.
 456                         #
 457                         # Guestimate if this is a continuing comment.  If this
 458                         # is the start of a diff block and this line starts
 459                         # ' *' then it is very likely a comment.
 460                         if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 461                                 $in_comment = 1;
 462                         }
 463                         if ($line =~ m@/\*@) {
 464                                 $in_comment = 1;
 465                         }
 466                         if ($line =~ m@\*/@) {
 467                                 $in_comment = 0;
 468                         }
 469
 470                         # Measure the line length and indent.
 471                         ($length, $indent) = line_stats($line);
 472
 473                         # Track the previous line.
 474                         ($prevline, $stashline) = ($stashline, $line);
 475                         ($previndent, $stashindent) = ($stashindent, $indent);
 476                 } elsif ($realcnt == 1) {
 477                         $realcnt--;
 478                 }
 479
 480 #make up the handle for any error we report on this line
 481                 $here = "#$linenr: ";
 482                 $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
 483
 484                 my $hereline = "$here\n$line\n";
 485                 my $herecurr = "$here\n$line\n";
 486                 my $hereprev = "$here\n$prevline\n$line\n";
 487
 488 #check the patch for a signoff:
 489                 if ($line =~ /^\s*signed-off-by:/i) {
 490                         # This is a signoff, if ugly, so do not double report.
 491                         $signoff++;
 492                         if (!($line =~ /^\s*Signed-off-by:/)) {
 493                                 WARN("Signed-off-by: is the preferred form\n" .
 494                                         $herecurr);
 495                         }
 496                         if ($line =~ /^\s*signed-off-by:\S/i) {
 497                                 WARN("need space after Signed-off-by:\n" .
 498                                         $herecurr);
 499                         }
 500                 }
 501
 502 # Check for wrappage within a valid hunk of the file
 503                 if ($realcnt != 0 && $line !~ m{^(?:\+|-| |$)}) {
 504                         ERROR("patch seems to be corrupt (line wrapped?)\n" .
 505                                 $herecurr);
 506                 }
 507
 508 # UTF-8 regex found at http://www.w3.org/International/questions/qa-forms-utf-8.en.php
 509                 if (($realfile =~ /^$/ || $line =~ /^\+/) &&
 510                      !($line =~ m/^(
 511                                 [\x09\x0A\x0D\x20-\x7E]              # ASCII
 512                                 | [\xC2-\xDF][\x80-\xBF]             # non-overlong 2-byte
 513                                 |  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
 514                                 | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
 515                                 |  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
 516                                 |  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
 517                                 | [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
 518                                 |  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
 519                                 )*$/x )) {
 520                         ERROR("Invalid UTF-8\n" . $herecurr);
 521                 }
 522
 523 #ignore lines being removed
 524                 if ($line=~/^-/) {next;}
 525
 526 # check we are in a valid source file if not then ignore this hunk
 527                 next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);
 528
 529 #trailing whitespace
 530                 if ($line =~ /^\+.*\015/) {
 531                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 532                         ERROR("DOS line endings\n" . $herevet);
 533
 534                 } elsif ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
 535                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 536                         ERROR("trailing whitespace\n" . $herevet);
 537                 }
 538 #80 column limit
 539                 if ($line =~ /^\+/ && !($prevline=~/\/\*\*/) && $length > 80) {
 540                         WARN("line over 80 characters\n" . $herecurr);
 541                 }
 542
 543 # check we are in a valid source file *.[hc] if not then ignore this hunk
 544                 next if ($realfile !~ /\.[hc]$/);
 545
 546 # at the beginning of a line any tabs must come first and anything
 547 # more than 8 must use tabs.
 548                 if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
 549                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 550                         ERROR("use tabs not spaces\n" . $herevet);
 551                 }
 552
 553 # Remove comments from the line before processing.
 554                 my $comment_edge = ($line =~ s@/\*.*\*/@@g) +
 555                                    ($line =~ s@/\*.*@@) +
 556                                    ($line =~ s@^(.).*\*/@$1@);
 557
 558 # The rest of our checks refer specifically to C style
 559 # only apply those _outside_ comments.  Only skip
 560 # lines in the middle of comments.
 561                 next if (!$comment_edge && $in_comment);
 562
 563 # Standardise the strings and chars within the input to simplify matching.
 564                 $line = sanitise_line($line);
 565
 566 # Check for potential 'bare' types
 567                 if ($realcnt &&
 568                     $line !~ /^.\s*(?:$Storage\s+)?(?:$Inline\s+)?$Type\b/ &&
 569                     $line !~ /$Ident:\s*$/ &&
 570                     $line !~ /^.\s*$Ident\s*\(/ &&
 571                     ($line =~ /^.(?:$Storage\s+)?(?:$Inline\s+)?($Ident)\b/ ||
 572                      $line =~ /^.\s*(?:$Storage\s+)?($Ident)\b\s*\**\s*$Ident\s*(?:;|=)/)) {
 573                         my $possible = $1;
 574                         if ($possible !~ /^(?:$Storage|$Type|DEFINE_\S+)$/ &&
 575                             $possible ne 'goto' && $possible ne 'return' &&
 576                             $possible ne 'struct' && $possible ne 'enum' &&
 577                             $possible ne 'case' && $possible ne 'else' &&
 578                             $possible ne 'typedef') {
 579                                 #print "POSSIBLE<$possible>\n";
 580                                 push(@bare, $possible);
 581                                 my $bare = join("|", @bare);
 582                                 $Bare   = qr{
 583                                                 \b(?:$bare)\b
 584                                                 (?:\s*\*+\s*const|\s*\*+|(?:\s*\[\s*\])+)?
 585                                                 (?:\s+$Sparse)*
 586                                           }x;
 587                         }
 588                 }
 589
 590 #
 591 # Checks which may be anchored in the context.
 592 #
 593
 594 # Check for switch () and associated case and default
 595 # statements should be at the same indent.
 596                 if ($line=~/\bswitch\s*\(.*\)/) {
 597                         my $err = '';
 598                         my $sep = '';
 599                         my @ctx = ctx_block_outer($linenr, $realcnt);
 600                         shift(@ctx);
 601                         for my $ctx (@ctx) {
 602                                 my ($clen, $cindent) = line_stats($ctx);
 603                                 if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
 604                                                         $indent != $cindent) {
 605                                         $err .= "$sep$ctx\n";
 606                                         $sep = '';
 607                                 } else {
 608                                         $sep = "[...]\n";
 609                                 }
 610                         }
 611                         if ($err ne '') {
 612                                 ERROR("switch and case should be at the same indent\n$hereline$err");
 613                         }
 614                 }
 615
 616 # if/while/etc brace do not go on next line, unless defining a do while loop,
 617 # or if that brace on the next line is for something else
 618                 if ($line =~ /\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.#/) {
 619                         my ($level, @ctx) = ctx_statement_level($linenr, $realcnt, 0);
 620                         my $ctx_ln = $linenr + $#ctx + 1;
 621                         my $ctx_cnt = $realcnt - $#ctx - 1;
 622                         my $ctx = join("\n", @ctx);
 623
 624                         # Skip over any removed lines in the context following statement.
 625                         while ($ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^-/) {
 626                                 $ctx_ln++;
 627                                 $ctx_cnt--;
 628                         }
 629                         ##warn "line<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>";
 630
 631                         if ($ctx !~ /{\s*/ && $ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
 632                                 ERROR("That open brace { should be on the previous line\n" .
 633                                         "$here\n$ctx\n$lines[$ctx_ln - 1]");
 634                         }
 635                         if ($level == 0 && $ctx =~ /\)\s*\;\s*$/ && defined $lines[$ctx_ln - 1]) {
 636                                 my ($nlength, $nindent) = line_stats($lines[$ctx_ln - 1]);
 637                                 if ($nindent > $indent) {
 638                                         WARN("Trailing semicolon indicates no statements, indent implies otherwise\n" .
 639                                                 "$here\n$ctx\n$lines[$ctx_ln - 1]");
 640                                 }
 641                         }
 642                 }
 643
 644 #ignore lines not being added
 645                 if ($line=~/^[^\+]/) {next;}
 646
 647 # TEST: allow direct testing of the type matcher.
 648                 if ($tst_type && $line =~ /^.$Declare$/) {
 649                         ERROR("TEST: is type $Declare\n" . $herecurr);
 650                         next;
 651                 }
 652
 653 # check for initialisation to aggregates open brace on the next line
 654                 if ($prevline =~ /$Declare\s*$Ident\s*=\s*$/ &&
 655                     $line =~ /^.\s*{/) {
 656                         ERROR("That open brace { should be on the previous line\n" . $hereprev);
 657                 }
 658
 659 #
 660 # Checks which are anchored on the added line.
 661 #
 662
 663 # check for malformed paths in #include statements (uses RAW line)
 664                 if ($rawline =~ m{^.#\s*include\s+[<"](.*)[">]}) {
 665                         my $path = $1;
 666                         if ($path =~ m{//}) {
 667                                 ERROR("malformed #include filename\n" .
 668                                         $herecurr);
 669                         }
 670                         # Sanitise this special form of string.
 671                         $path = 'X' x length($path);
 672                         $line =~ s{\<.*\>}{<$path>};
 673                 }
 674
 675 # no C99 // comments
 676                 if ($line =~ m{//}) {
 677                         ERROR("do not use C99 // comments\n" . $herecurr);
 678                 }
 679                 # Remove C99 comments.
 680                 $line =~ s@//.*@@;
 681
 682 #EXPORT_SYMBOL should immediately follow its function closing }.
 683                 if (($line =~ /EXPORT_SYMBOL.*\((.*)\)/) ||
 684                     ($line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
 685                         my $name = $1;
 686                         if (($prevline !~ /^}/) &&
 687                            ($prevline !~ /^\+}/) &&
 688                            ($prevline !~ /^ }/) &&
 689                            ($prevline !~ /\b\Q$name\E(?:\s+$Attribute)?\s*(?:;|=)/)) {
 690                                 WARN("EXPORT_SYMBOL(foo); should immediately follow its function/variable\n" . $herecurr);
 691                         }
 692                 }
 693
 694 # check for external initialisers.
 695                 if ($line =~ /^.$Type\s*$Ident\s*=\s*(0|NULL);/) {
 696                         ERROR("do not initialise externals to 0 or NULL\n" .
 697                                 $herecurr);
 698                 }
 699 # check for static initialisers.
 700                 if ($line =~ /\s*static\s.*=\s*(0|NULL);/) {
 701                         ERROR("do not initialise statics to 0 or NULL\n" .
 702                                 $herecurr);
 703                 }
 704
 705 # check for new typedefs, only function parameters and sparse annotations
 706 # make sense.
 707                 if ($line =~ /\btypedef\s/ &&
 708                     $line !~ /\btypedef\s+$Type\s+\(\s*\*?$Ident\s*\)\s*\(/ &&
 709                     $line !~ /\b__bitwise(?:__|)\b/) {
 710                         WARN("do not add new typedefs\n" . $herecurr);
 711                 }
 712
 713 # * goes on variable not on type
 714                 if ($line =~ m{\($NonptrType(\*+)(?:\s+const)?\)}) {
 715                         ERROR("\"(foo$1)\" should be \"(foo $1)\"\n" .
 716                                 $herecurr);
 717
 718                 } elsif ($line =~ m{\($NonptrType\s+(\*+)(?!\s+const)\s+\)}) {
 719                         ERROR("\"(foo $1 )\" should be \"(foo $1)\"\n" .
 720                                 $herecurr);
 721
 722                 } elsif ($line =~ m{$NonptrType(\*+)(?:\s+(?:$Attribute|$Sparse))?\s+[A-Za-z\d_]+}) {
 723                         ERROR("\"foo$1 bar\" should be \"foo $1bar\"\n" .
 724                                 $herecurr);
 725
 726                 } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+(?:$Attribute|$Sparse))\s+[A-Za-z\d_]+}) {
 727                         ERROR("\"foo $1 bar\" should be \"foo $1bar\"\n" .
 728                                 $herecurr);
 729                 }
 730
 731 # # no BUG() or BUG_ON()
 732 #               if ($line =~ /\b(BUG|BUG_ON)\b/) {
 733 #                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
 734 #                       print "$herecurr";
 735 #                       $clean = 0;
 736 #               }
 737
 738 # printk should use KERN_* levels.  Note that follow on printk's on the
 739 # same line do not need a level, so we use the current block context
 740 # to try and find and validate the current printk.  In summary the current
 741 # printk includes all preceeding printk's which have no newline on the end.
 742 # we assume the first bad printk is the one to report.
 743                 if ($line =~ /\bprintk\((?!KERN_)\s*"/) {
 744                         my $ok = 0;
 745                         for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
 746                                 #print "CHECK<$lines[$ln - 1]\n";
 747                                 # we have a preceeding printk if it ends
 748                                 # with "\n" ignore it, else it is to blame
 749                                 if ($lines[$ln - 1] =~ m{\bprintk\(}) {
 750                                         if ($rawlines[$ln - 1] !~ m{\\n"}) {
 751                                                 $ok = 1;
 752                                         }
 753                                         last;
 754                                 }
 755                         }
 756                         if ($ok == 0) {
 757                                 WARN("printk() should include KERN_ facility level\n" . $herecurr);
 758                         }
 759                 }
 760
 761 # function brace can't be on same line, except for #defines of do while,
 762 # or if closed on same line
 763                 if (($line=~/$Type\s*[A-Za-z\d_]+\(.*\).* {/) and
 764                     !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
 765                         ERROR("open brace '{' following function declarations go on the next line\n" . $herecurr);
 766                 }
 767
 768 # check for spaces between functions and their parentheses.
 769                 if ($line =~ /($Ident)\s+\(/ &&
 770                     $1 !~ /^(?:if|for|while|switch|return|volatile|__volatile__|__attribute__|format|__extension__|Copyright)$/ &&
 771                     $line !~ /$Type\s+\(/ && $line !~ /^.\#\s*define\b/) {
 772                         WARN("no space between function name and open parenthesis '('\n" . $herecurr);
 773                 }
 774 # Check operator spacing.
 775                 # Note we expand the line with the leading + as the real
 776                 # line will be displayed with the leading + and the tabs
 777                 # will therefore also expand that way.
 778                 my $opline = $line;
 779                 $opline = expand_tabs($opline);
 780                 $opline =~ s/^./ /;
 781                 if (!($line=~/\#\s*include/)) {
 782                         my $ops = qr{
 783                                 <<=|>>=|<=|>=|==|!=|
 784                                 \+=|-=|\*=|\/=|%=|\^=|\|=|&=|
 785                                 =>|->|<<|>>|<|>|=|!|~|
 786                                 &&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/
 787                         }x;
 788                         my @elements = split(/($ops|;)/, $opline);
 789                         my $off = 0;
 790                         for (my $n = 0; $n < $#elements; $n += 2) {
 791                                 $off += length($elements[$n]);
 792
 793                                 my $a = '';
 794                                 $a = 'V' if ($elements[$n] ne '');
 795                                 $a = 'W' if ($elements[$n] =~ /\s$/);
 796                                 $a = 'B' if ($elements[$n] =~ /(\[|\()$/);
 797                                 $a = 'O' if ($elements[$n] eq '');
 798                                 $a = 'E' if ($elements[$n] eq '' && $n == 0);
 799
 800                                 my $op = $elements[$n + 1];
 801
 802                                 my $c = '';
 803                                 if (defined $elements[$n + 2]) {
 804                                         $c = 'V' if ($elements[$n + 2] ne '');
 805                                         $c = 'W' if ($elements[$n + 2] =~ /^\s/);
 806                                         $c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
 807                                         $c = 'O' if ($elements[$n + 2] eq '');
 808                                         $c = 'E' if ($elements[$n + 2] =~ /\s*\\$/);
 809                                 } else {
 810                                         $c = 'E';
 811                                 }
 812
 813                                 # Pick up the preceeding and succeeding characters.
 814                                 my $ca = substr($opline, 0, $off);
 815                                 my $cc = '';
 816                                 if (length($opline) >= ($off + length($elements[$n + 1]))) {
 817                                         $cc = substr($opline, $off + length($elements[$n + 1]));
 818                                 }
 819                                 my $cb = "$ca$;$cc";
 820
 821                                 my $ctx = "${a}x${c}";
 822
 823                                 my $at = "(ctx:$ctx)";
 824
 825                                 my $ptr = (" " x $off) . "^";
 826                                 my $hereptr = "$hereline$ptr\n";
 827
 828                                 # Classify operators into binary, unary, or
 829                                 # definitions (* only) where they have more
 830                                 # than one mode.
 831                                 my $unary_ctx = $prevline . $ca;
 832                                 $unary_ctx =~ s/^./ /;
 833                                 my $is_unary = 0;
 834                                 my $Unary = qr{
 835                                         (?:
 836                                                 ^|;|,|$ops|\(|\?|:|
 837                                                 \(\s*$Type\s*\)|
 838                                                 $Type|
 839                                                 return|case|else|
 840                                                 \{|\}|
 841                                                 \[|
 842                                                 ^.\#\s*define\s+$Ident\s*(?:\([^\)]*\))?|
 843                                                 ^.\#\s*else|
 844                                                 ^.\#\s*endif|
 845                                                 ^.\#\s*(?:if|ifndef|ifdef)\b.*
 846                                         )\s*(?:|\\)\s*$
 847                                 }x;
 848                                 my $UnaryFalse = qr{
 849                                         sizeof\s*\(\s*$Type\s*\)\s*$
 850                                 }x;
 851                                 my $UnaryDefine = qr{
 852                                          (?:$Type|$Bare)\s*|
 853                                          (?:$Type|$Bare).*,\s*\**
 854                                 }x;
 855                                 if ($op eq '-' || $op eq '&' || $op eq '*') {
 856                                         # An operator is binary if the left hand
 857                                         # side is a value.  Pick out the known
 858                                         # non-values.
 859                                         if ($unary_ctx =~ /$Unary$/s &&
 860                                             $unary_ctx !~ /$UnaryFalse$/s) {
 861                                                 $is_unary = 1;
 862
 863                                         # Special handling for ')' check if this
 864                                         # brace represents a conditional, if so
 865                                         # we are unary.
 866                                         } elsif ($unary_ctx =~ /\)\s*$/) {
 867                                                 my $before = ctx_expr_before($unary_ctx);
 868                                                 if ($before =~ /(?:for|if|while)\s*$/) {
 869                                                         $is_unary = 1;
 870                                                 }
 871                                         }
 872
 873                                         # Check for type definition for of '*'.
 874                                         if ($op eq '*' && $unary_ctx =~ /$UnaryDefine$/) {
 875                                                 $is_unary = 2;
 876                                         }
 877                                 }
 878
 879                                 #if ($op eq '-' || $op eq '&' || $op eq '*') {
 880                                 #       print "UNARY: <$is_unary $a:$op:$c> <$ca:$op:$cc> <$unary_ctx>\n";
 881                                 #}
 882
 883                                 # ; should have either the end of line or a space or \ after it
 884                                 if ($op eq ';') {
 885                                         if ($ctx !~ /.x[WEB]/ && $cc !~ /^\\/ &&
 886                                             $cc !~ /^;/) {
 887                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
 888                                         }
 889
 890                                 # // is a comment
 891                                 } elsif ($op eq '//') {
 892
 893                                 # -> should have no spaces
 894                                 } elsif ($op eq '->') {
 895                                         if ($ctx =~ /Wx.|.xW/) {
 896                                                 ERROR("no spaces around that '$op' $at\n" . $hereptr);
 897                                         }
 898
 899                                 # , must have a space on the right.
 900                                 } elsif ($op eq ',') {
 901                                         if ($ctx !~ /.xW|.xE/ && $cc !~ /^}/) {
 902                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
 903                                         }
 904
 905                                 # '*' as part of a type definition -- reported already.
 906                                 } elsif ($op eq '*' && $is_unary == 2) {
 907                                         #warn "'*' is part of type\n";
 908
 909                                 # unary operators should have a space before and
 910                                 # none after.  May be left adjacent to another
 911                                 # unary operator, or a cast
 912                                 } elsif ($op eq '!' || $op eq '~' ||
 913                                          ($is_unary && ($op eq '*' || $op eq '-' || $op eq '&'))) {
 914                                         if ($ctx !~ /[WEB]x./ && $ca !~ /(?:\)|!|~|\*|-|\&|\||\+\+|\-\-|\{)$/) {
 915                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 916                                         }
 917                                         if ($ctx =~ /.xW/) {
 918                                                 ERROR("no space after that '$op' $at\n" . $hereptr);
 919                                         }
 920
 921                                 # unary ++ and unary -- are allowed no space on one side.
 922                                 } elsif ($op eq '++' or $op eq '--') {
 923                                         if ($ctx !~ /[WOB]x[^W]/ && $ctx !~ /[^W]x[WOBE]/) {
 924                                                 ERROR("need space one side of that '$op' $at\n" . $hereptr);
 925                                         }
 926                                         if ($ctx =~ /Wx./ && $cc =~ /^;/) {
 927                                                 ERROR("no space before that '$op' $at\n" . $hereptr);
 928                                         }
 929
 930                                 # << and >> may either have or not have spaces both sides
 931                                 } elsif ($op eq '<<' or $op eq '>>' or
 932                                          $op eq '&' or $op eq '^' or $op eq '|' or
 933                                          $op eq '+' or $op eq '-' or
 934                                          $op eq '*' or $op eq '/')
 935                                 {
 936                                         if ($ctx !~ /VxV|WxW|VxE|WxE|VxO/) {
 937                                                 ERROR("need consistent spacing around '$op' $at\n" .
 938                                                         $hereptr);
 939                                         }
 940
 941                                 # All the others need spaces both sides.
 942                                 } elsif ($ctx !~ /[EW]x[WE]/) {
 943                                         # Ignore email addresses <foo@bar>
 944                                         if (!($op eq '<' && $cb =~ /$;\S+\@\S+>/) &&
 945                                             !($op eq '>' && $cb =~ /<\S+\@\S+$;/)) {
 946                                                 ERROR("need spaces around that '$op' $at\n" . $hereptr);
 947                                         }
 948                                 }
 949                                 $off += length($elements[$n + 1]);
 950                         }
 951                 }
 952
 953 # check for multiple assignments
 954                 if ($line =~ /^.\s*$Lval\s*=\s*$Lval\s*=(?!=)/) {
 955                         WARN("multiple assignments should be avoided\n" . $herecurr);
 956                 }
 957
 958 ## # check for multiple declarations, allowing for a function declaration
 959 ## # continuation.
 960 ##              if ($line =~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Ident.*/ &&
 961 ##                  $line !~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Type\s*$Ident.*/) {
 962 ##
 963 ##                      # Remove any bracketed sections to ensure we do not
 964 ##                      # falsly report the parameters of functions.
 965 ##                      my $ln = $line;
 966 ##                      while ($ln =~ s/\([^\(\)]*\)//g) {
 967 ##                      }
 968 ##                      if ($ln =~ /,/) {
 969 ##                              WARN("declaring multiple variables together should be avoided\n" . $herecurr);
 970 ##                      }
 971 ##              }
 972
 973 #need space before brace following if, while, etc
 974                 if (($line =~ /\(.*\){/ && $line !~ /\($Type\){/) ||
 975                     $line =~ /do{/) {
 976                         ERROR("need a space before the open brace '{'\n" . $herecurr);
 977                 }
 978
 979 # closing brace should have a space following it when it has anything
 980 # on the line
 981                 if ($line =~ /}(?!(?:,|;|\)))\S/) {
 982                         ERROR("need a space after that close brace '}'\n" . $herecurr);
 983                 }
 984
 985 # check spacing on square brackets
 986                 if ($line =~ /\[\s/ && $line !~ /\[\s*$/) {
 987                         ERROR("no space after that open square bracket '['\n" . $herecurr);
 988                 }
 989                 if ($line =~ /\s\]/) {
 990                         ERROR("no space before that close square bracket ']'\n" . $herecurr);
 991                 }
 992
 993 # check spacing on paretheses
 994                 if ($line =~ /\(\s/ && $line !~ /\(\s*(?:\\)?$/ &&
 995                     $line !~ /for\s*\(\s+;/) {
 996                         ERROR("no space after that open parenthesis '('\n" . $herecurr);
 997                 }
 998                 if ($line =~ /\s\)/ && $line !~ /^.\s*\)/ &&
 999                     $line !~ /for\s*\(.*;\s+\)/) {
1000                         ERROR("no space before that close parenthesis ')'\n" . $herecurr);
1001                 }
1002
1003 #goto labels aren't indented, allow a single space however
1004                 if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
1005                    !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
1006                         WARN("labels should not be indented\n" . $herecurr);
1007                 }
1008
1009 # Need a space before open parenthesis after if, while etc
1010                 if ($line=~/\b(if|while|for|switch)\(/) {
1011                         ERROR("need a space before the open parenthesis '('\n" . $herecurr);
1012                 }
1013
1014 # Check for illegal assignment in if conditional.
1015                 if ($line=~/\bif\s*\(.*[^<>!=]=[^=].*\)/) {
1016                         #next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
1017                         ERROR("do not use assignment in if condition\n" . $herecurr);
1018                 }
1019
1020                 # Check for }<nl>else {, these must be at the same
1021                 # indent level to be relevant to each other.
1022                 if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
1023                                                 $previndent == $indent) {
1024                         ERROR("else should follow close brace '}'\n" . $hereprev);
1025                 }
1026
1027 #studly caps, commented out until figure out how to distinguish between use of existing and adding new
1028 #               if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
1029 #                   print "No studly caps, use _\n";
1030 #                   print "$herecurr";
1031 #                   $clean = 0;
1032 #               }
1033
1034 #no spaces allowed after \ in define
1035                 if ($line=~/\#define.*\\\s$/) {
1036                         WARN("Whitepspace after \\ makes next lines useless\n" . $herecurr);
1037                 }
1038
1039 #warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
1040                 if ($tree && $rawline =~ m{^.\#\s*include\s*\<asm\/(.*)\.h\>}) {
1041                         my $checkfile = "include/linux/$1.h";
1042                         if (-f $checkfile) {
1043                                 CHK("Use #include <linux/$1.h> instead of <asm/$1.h>\n" .
1044                                         $herecurr);
1045                         }
1046                 }
1047
1048 # if and else should not have general statements after it
1049                 if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/ &&
1050                     $1 !~ /^\s*(?:\sif|{|\\|$)/) {
1051                         ERROR("trailing statements should be on next line\n" . $herecurr);
1052                 }
1053
1054 # multi-statement macros should be enclosed in a do while loop, grab the
1055 # first statement and ensure its the whole macro if its not enclosed
1056 # in a known goot container
1057                 if ($prevline =~ /\#define.*\\/ &&
1058                    $prevline !~/(?:do\s+{|\(\{|\{)/ &&
1059                    $line !~ /(?:do\s+{|\(\{|\{)/ &&
1060                    $line !~ /^.\s*$Declare\s/) {
1061                         # Grab the first statement, if that is the entire macro
1062                         # its ok.  This may start either on the #define line
1063                         # or the one below.
1064                         my $ln = $linenr;
1065                         my $cnt = $realcnt;
1066                         my $off = 0;
1067
1068                         # If the macro starts on the define line start
1069                         # grabbing the statement after the identifier
1070                         $prevline =~ m{^(.#\s*define\s*$Ident(?:\([^\)]*\))?\s*)(.*)\\\s*$};
1071                         ##print "1<$1> 2<$2>\n";
1072                         if (defined $2 && $2 ne '') {
1073                                 $off = length($1);
1074                                 $ln--;
1075                                 $cnt++;
1076                         }
1077                         my @ctx = ctx_statement($ln, $cnt, $off);
1078                         my $ctx_ln = $ln + $#ctx + 1;
1079                         my $ctx = join("\n", @ctx);
1080
1081                         # Pull in any empty extension lines.
1082                         while ($ctx =~ /\\$/ &&
1083                                $lines[$ctx_ln - 1] =~ /^.\s*(?:\\)?$/) {
1084                                 $ctx .= $lines[$ctx_ln - 1];
1085                                 $ctx_ln++;
1086                         }
1087
1088                         if ($ctx =~ /\\$/) {
1089                                 if ($ctx =~ /;/) {
1090                                         ERROR("Macros with multiple statements should be enclosed in a do - while loop\n" . "$here\n$ctx\n");
1091                                 } else {
1092                                         ERROR("Macros with complex values should be enclosed in parenthesis\n" . "$here\n$ctx\n");
1093                                 }
1094                         }
1095                 }
1096
1097 # check for redundant bracing round if etc
1098                 if ($line =~ /\b(if|while|for|else)\b/) {
1099                         # Locate the end of the opening statement.
1100                         my @control = ctx_statement($linenr, $realcnt, 0);
1101                         my $nr = $linenr + (scalar(@control) - 1);
1102                         my $cnt = $realcnt - (scalar(@control) - 1);
1103
1104                         my $off = $realcnt - $cnt;
1105                         #print "$off: line<$line>end<" . $lines[$nr - 1] . ">\n";
1106
1107                         # If this is is a braced statement group check it
1108                         if ($lines[$nr - 1] =~ /{\s*$/) {
1109                                 my ($lvl, @block) = ctx_block_level($nr, $cnt);
1110
1111                                 my $stmt = join(' ', @block);
1112                                 $stmt =~ s/(^[^{]*){//;
1113                                 my $before = $1;
1114                                 $stmt =~ s/}([^}]*$)//;
1115                                 my $after = $1;
1116
1117                                 #print "block<" . join(' ', @block) . "><" . scalar(@block) . ">\n";
1118                                 #print "stmt<$stmt>\n\n";
1119
1120                                 # Count the ;'s if there is fewer than two
1121                                 # then there can only be one statement,
1122                                 # if there is a brace inside we cannot
1123                                 # trivially detect if its one statement.
1124                                 # Also nested if's often require braces to
1125                                 # disambiguate the else binding so shhh there.
1126                                 my @semi = ($stmt =~ /;/g);
1127                                 push(@semi, "/**/") if ($stmt =~ m@/\*@);
1128                                 ##print "semi<" . scalar(@semi) . ">\n";
1129                                 if ($lvl == 0 && scalar(@semi) < 2 &&
1130                                     $stmt !~ /{/ && $stmt !~ /\bif\b/ &&
1131                                     $before !~ /}/ && $after !~ /{/) {
1132                                         my $herectx = "$here\n" . join("\n", @control, @block[1 .. $#block]) . "\n";
1133                                         shift(@block);
1134                                         WARN("braces {} are not necessary for single statement blocks\n" . $herectx);
1135                                 }
1136                         }
1137                 }
1138
1139 # don't include deprecated include files (uses RAW line)
1140                 for my $inc (@dep_includes) {
1141                         if ($rawline =~ m@\#\s*include\s*\<$inc>@) {
1142                                 ERROR("Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n" . $herecurr);
1143                         }
1144                 }
1145
1146 # don't use deprecated functions
1147                 for my $func (@dep_functions) {
1148                         if ($line =~ /\b$func\b/) {
1149                                 ERROR("Don't use $func(): see Documentation/feature-removal-schedule.txt\n" . $herecurr);
1150                         }
1151                 }
1152
1153 # no volatiles please
1154                 if ($line =~ /\bvolatile\b/ && $line !~ /\basm\s+volatile\b/) {
1155                         WARN("Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n" . $herecurr);
1156                 }
1157
1158 # SPIN_LOCK_UNLOCKED & RW_LOCK_UNLOCKED are deprecated
1159                 if ($line =~ /\b(SPIN_LOCK_UNLOCKED|RW_LOCK_UNLOCKED)/) {
1160                         ERROR("Use of $1 is deprecated: see Documentation/spinlocks.txt\n" . $herecurr);
1161                 }
1162
1163 # warn about #if 0
1164                 if ($line =~ /^.#\s*if\s+0\b/) {
1165                         CHK("if this code is redundant consider removing it\n" .
1166                                 $herecurr);
1167                 }
1168
1169 # check for needless kfree() checks
1170                 if ($prevline =~ /\bif\s*\(([^\)]*)\)/) {
1171                         my $expr = $1;
1172                         if ($line =~ /\bkfree\(\Q$expr\E\);/) {
1173                                 WARN("kfree(NULL) is safe this check is probabally not required\n" . $hereprev);
1174                         }
1175                 }
1176
1177 # warn about #ifdefs in C files
1178 #               if ($line =~ /^.#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
1179 #                       print "#ifdef in C files should be avoided\n";
1180 #                       print "$herecurr";
1181 #                       $clean = 0;
1182 #               }
1183
1184 # warn about spacing in #ifdefs
1185                 if ($line =~ /^.#\s*(ifdef|ifndef|elif)\s\s+/) {
1186                         ERROR("exactly one space required after that #$1\n" . $herecurr);
1187                 }
1188
1189 # check for spinlock_t definitions without a comment.
1190                 if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/) {
1191                         my $which = $1;
1192                         if (!ctx_has_comment($first_line, $linenr)) {
1193                                 CHK("$1 definition without comment\n" . $herecurr);
1194                         }
1195                 }
1196 # check for memory barriers without a comment.
1197                 if ($line =~ /\b(mb|rmb|wmb|read_barrier_depends|smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
1198                         if (!ctx_has_comment($first_line, $linenr)) {
1199                                 CHK("memory barrier without comment\n" . $herecurr);
1200                         }
1201                 }
1202 # check of hardware specific defines
1203                 if ($line =~ m@^.#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@ && $realfile !~ m@include/asm-@) {
1204                         CHK("architecture specific defines should be avoided\n" .  $herecurr);
1205                 }
1206
1207 # check the location of the inline attribute, that it is between
1208 # storage class and type.
1209                 if ($line =~ /\b$Type\s+$Inline\b/ ||
1210                     $line =~ /\b$Inline\s+$Storage\b/) {
1211                         ERROR("inline keyword should sit between storage class and type\n" . $herecurr);
1212                 }
1213
1214 # check for new externs in .c files.
1215                 if ($line =~ /^.\s*extern\s/ && ($realfile =~ /\.c$/)) {
1216                         WARN("externs should be avoided in .c files\n" .  $herecurr);
1217                 }
1218
1219 # checks for new __setup's
1220                 if ($rawline =~ /\b__setup\("([^"]*)"/) {
1221                         my $name = $1;
1222
1223                         if (!grep(/$name/, @setup_docs)) {
1224                                 CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
1225                         }
1226                 }
1227
1228 # check for pointless casting of kmalloc return
1229                 if ($line =~ /\*\s*\)\s*k[czm]alloc\b/) {
1230                         WARN("unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);
1231                 }
1232         }
1233
1234         if ($chk_patch && !$is_patch) {
1235                 ERROR("Does not appear to be a unified-diff format patch\n");
1236         }
1237         if ($is_patch && $chk_signoff && $signoff == 0) {
1238                 ERROR("Missing Signed-off-by: line(s)\n");
1239         }
1240
1241         if ($clean == 0 && ($chk_patch || $is_patch)) {
1242                 print report_dump();
1243         }
1244         if ($clean == 1 && $quiet == 0) {
1245                 print "Your patch has no obvious style problems and is ready for submission.\n"
1246         }
1247         if ($clean == 0 && $quiet == 0) {
1248                 print "Your patch has style problems, please review.  If any of these errors\n";
1249                 print "are false positives report them to the maintainer, see\n";
1250                 print "CHECKPATCH in MAINTAINERS.\n";
1251         }
1252         return $clean;
1253 }