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 = '0.07';
  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 (/^Files:\s+(.*\S)/) {
  51                         for my $file (split(/[, ]+/, $1)) {
  52                                 if ($file =~ m@include/(.*)@) {
  53                                         push(@dep_includes, $1);
  54                                 }
  55                         }
  56
  57                 } elsif (/^Funcs:\s+(.*\S)/) {
  58                         for my $func (split(/[, ]+/, $1)) {
  59                                 push(@dep_functions, $func);
  60                         }
  61                 }
  62         }
  63 }
  64
  65 my @rawlines = ();
  66 while (<>) {
  67         chomp;
  68         push(@rawlines, $_);
  69         if (eof(ARGV)) {
  70                 if (!process($ARGV, @rawlines)) {
  71                         $exit = 1;
  72                 }
  73                 @rawlines = ();
  74         }
  75 }
  76
  77 exit($exit);
  78
  79 sub top_of_kernel_tree {
  80         if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
  81             (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
  82             (-d "Documentation") && (-d "arch") && (-d "include") &&
  83             (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
  84             (-d "kernel") && (-d "lib") && (-d "scripts")) {
  85                 return 1;
  86         }
  87         return 0;
  88 }
  89
  90 sub expand_tabs {
  91         my ($str) = @_;
  92
  93         my $res = '';
  94         my $n = 0;
  95         for my $c (split(//, $str)) {
  96                 if ($c eq "\t") {
  97                         $res .= ' ';
  98                         $n++;
  99                         for (; ($n % 8) != 0; $n++) {
 100                                 $res .= ' ';
 101                         }
 102                         next;
 103                 }
 104                 $res .= $c;
 105                 $n++;
 106         }
 107
 108         return $res;
 109 }
 110
 111 sub line_stats {
 112         my ($line) = @_;
 113
 114         # Drop the diff line leader and expand tabs
 115         $line =~ s/^.//;
 116         $line = expand_tabs($line);
 117
 118         # Pick the indent from the front of the line.
 119         my ($white) = ($line =~ /^(\s*)/);
 120
 121         return (length($line), length($white));
 122 }
 123
 124 sub sanitise_line {
 125         my ($line) = @_;
 126
 127         my $res = '';
 128         my $l = '';
 129
 130         my $quote = '';
 131
 132         foreach my $c (split(//, $line)) {
 133                 if ($l ne "\\" && ($c eq "'" || $c eq '"')) {
 134                         if ($quote eq '') {
 135                                 $quote = $c;
 136                                 $res .= $c;
 137                                 $l = $c;
 138                                 next;
 139                         } elsif ($quote eq $c) {
 140                                 $quote = '';
 141                         }
 142                 }
 143                 if ($quote && $c ne "\t") {
 144                         $res .= "X";
 145                 } else {
 146                         $res .= $c;
 147                 }
 148
 149                 $l = $c;
 150         }
 151
 152         return $res;
 153 }
 154
 155 sub ctx_block_get {
 156         my ($linenr, $remain, $outer, $open, $close) = @_;
 157         my $line;
 158         my $start = $linenr - 1;
 159         my $blk = '';
 160         my @o;
 161         my @c;
 162         my @res = ();
 163
 164         for ($line = $start; $remain > 0; $line++) {
 165                 next if ($rawlines[$line] =~ /^-/);
 166                 $remain--;
 167
 168                 $blk .= $rawlines[$line];
 169
 170                 @o = ($blk =~ /$open/g);
 171                 @c = ($blk =~ /$close/g);
 172
 173                 if (!$outer || (scalar(@o) - scalar(@c)) == 1) {
 174                         push(@res, $rawlines[$line]);
 175                 }
 176
 177                 last if (scalar(@o) == scalar(@c));
 178         }
 179
 180         return @res;
 181 }
 182 sub ctx_block_outer {
 183         my ($linenr, $remain) = @_;
 184
 185         return ctx_block_get($linenr, $remain, 1, '\{', '\}');
 186 }
 187 sub ctx_block {
 188         my ($linenr, $remain) = @_;
 189
 190         return ctx_block_get($linenr, $remain, 0, '\{', '\}');
 191 }
 192 sub ctx_statement {
 193         my ($linenr, $remain) = @_;
 194
 195         return ctx_block_get($linenr, $remain, 0, '\(', '\)');
 196 }
 197
 198 sub ctx_locate_comment {
 199         my ($first_line, $end_line) = @_;
 200
 201         # Catch a comment on the end of the line itself.
 202         my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*$@);
 203         return $current_comment if (defined $current_comment);
 204
 205         # Look through the context and try and figure out if there is a
 206         # comment.
 207         my $in_comment = 0;
 208         $current_comment = '';
 209         for (my $linenr = $first_line; $linenr < $end_line; $linenr++) {
 210                 my $line = $rawlines[$linenr - 1];
 211                 #warn "           $line\n";
 212                 if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 213                         $in_comment = 1;
 214                 }
 215                 if ($line =~ m@/\*@) {
 216                         $in_comment = 1;
 217                 }
 218                 if (!$in_comment && $current_comment ne '') {
 219                         $current_comment = '';
 220                 }
 221                 $current_comment .= $line . "\n" if ($in_comment);
 222                 if ($line =~ m@\*/@) {
 223                         $in_comment = 0;
 224                 }
 225         }
 226
 227         chomp($current_comment);
 228         return($current_comment);
 229 }
 230 sub ctx_has_comment {
 231         my ($first_line, $end_line) = @_;
 232         my $cmt = ctx_locate_comment($first_line, $end_line);
 233
 234         ##print "LINE: $rawlines[$end_line - 1 ]\n";
 235         ##print "CMMT: $cmt\n";
 236
 237         return ($cmt ne '');
 238 }
 239
 240 sub cat_vet {
 241         my ($vet) = @_;
 242
 243         $vet =~ s/\t/^I/;
 244         $vet =~ s/$/\$/;
 245
 246         return $vet;
 247 }
 248
 249 sub ERROR {
 250         print "ERROR: $_[0]\n";
 251         our $clean = 0;
 252 }
 253 sub WARN {
 254         print "WARNING: $_[0]\n";
 255         our $clean = 0;
 256 }
 257 sub CHK {
 258         print "CHECK: $_[0]\n";
 259         our $clean = 0;
 260 }
 261
 262 sub process {
 263         my $filename = shift;
 264         my @lines = @_;
 265
 266         my $linenr=0;
 267         my $prevline="";
 268         my $stashline="";
 269
 270         my $length;
 271         my $indent;
 272         my $previndent=0;
 273         my $stashindent=0;
 274
 275         our $clean = 1;
 276         my $signoff = 0;
 277         my $is_patch = 0;
 278
 279         # Trace the real file/line as we go.
 280         my $realfile = '';
 281         my $realline = 0;
 282         my $realcnt = 0;
 283         my $here = '';
 284         my $in_comment = 0;
 285         my $first_line = 0;
 286
 287         my $Ident       = qr{[A-Za-z\d_]+};
 288         my $Storage     = qr{extern|static};
 289         my $Sparse      = qr{__user|__kernel|__force|__iomem};
 290         my $NonptrType  = qr{
 291                                 \b
 292                                 (?:const\s+)?
 293                                 (?:unsigned\s+)?
 294                                 (?:
 295                                         void|
 296                                         char|
 297                                         short|
 298                                         int|
 299                                         long|
 300                                         unsigned|
 301                                         float|
 302                                         double|
 303                                         long\s+int|
 304                                         long\s+long|
 305                                         long\s+long\s+int|
 306                                         u8|u16|u32|u64|
 307                                         s8|s16|s32|s64|
 308                                         struct\s+$Ident|
 309                                         union\s+$Ident|
 310                                         enum\s+$Ident|
 311                                         ${Ident}_t
 312                                 )
 313                                 (?:\s+$Sparse)*
 314                                 \b
 315                           }x;
 316         my $Type        = qr{
 317                                 \b$NonptrType\b
 318                                 (?:\s*\*+\s*const|\s*\*+)?
 319                           }x;
 320         my $Declare     = qr{(?:$Storage\s+)?$Type};
 321         my $Attribute   = qr{__read_mostly|__init|__initdata};
 322
 323         # Pre-scan the patch looking for any __setup documentation.
 324         my @setup_docs = ();
 325         my $setup_docs = 0;
 326         foreach my $line (@lines) {
 327                 if ($line=~/^\+\+\+\s+(\S+)/) {
 328                         $setup_docs = 0;
 329                         if ($1 =~ m@Documentation/kernel-parameters.txt$@) {
 330                                 $setup_docs = 1;
 331                         }
 332                         next;
 333                 }
 334
 335                 if ($setup_docs && $line =~ /^\+/) {
 336                         push(@setup_docs, $line);
 337                 }
 338         }
 339
 340         foreach my $line (@lines) {
 341                 $linenr++;
 342
 343                 my $rawline = $line;
 344
 345 #extract the filename as it passes
 346                 if ($line=~/^\+\+\+\s+(\S+)/) {
 347                         $realfile=$1;
 348                         $realfile =~ s@^[^/]*/@@;
 349                         $in_comment = 0;
 350                         next;
 351                 }
 352 #extract the line range in the file after the patch is applied
 353                 if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
 354                         $is_patch = 1;
 355                         $first_line = $linenr + 1;
 356                         $in_comment = 0;
 357                         $realline=$1-1;
 358                         if (defined $2) {
 359                                 $realcnt=$3+1;
 360                         } else {
 361                                 $realcnt=1+1;
 362                         }
 363                         next;
 364                 }
 365
 366 # track the line number as we move through the hunk, note that
 367 # new versions of GNU diff omit the leading space on completely
 368 # blank context lines so we need to count that too.
 369                 if ($line =~ /^( |\+|$)/) {
 370                         $realline++;
 371                         $realcnt-- if ($realcnt != 0);
 372
 373                         # track any sort of multi-line comment.  Obviously if
 374                         # the added text or context do not include the whole
 375                         # comment we will not see it. Such is life.
 376                         #
 377                         # Guestimate if this is a continuing comment.  If this
 378                         # is the start of a diff block and this line starts
 379                         # ' *' then it is very likely a comment.
 380                         if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 381                                 $in_comment = 1;
 382                         }
 383                         if ($line =~ m@/\*@) {
 384                                 $in_comment = 1;
 385                         }
 386                         if ($line =~ m@\*/@) {
 387                                 $in_comment = 0;
 388                         }
 389
 390                         # Measure the line length and indent.
 391                         ($length, $indent) = line_stats($line);
 392
 393                         # Track the previous line.
 394                         ($prevline, $stashline) = ($stashline, $line);
 395                         ($previndent, $stashindent) = ($stashindent, $indent);
 396                 } elsif ($realcnt == 1) {
 397                         $realcnt--;
 398                 }
 399
 400 #make up the handle for any error we report on this line
 401                 $here = "#$linenr: ";
 402                 $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
 403
 404                 my $hereline = "$here\n$line\n";
 405                 my $herecurr = "$here\n$line\n";
 406                 my $hereprev = "$here\n$prevline\n$line\n";
 407
 408 #check the patch for a signoff:
 409                 if ($line =~ /^\s*signed-off-by:/i) {
 410                         # This is a signoff, if ugly, so do not double report.
 411                         $signoff++;
 412                         if (!($line =~ /^\s*Signed-off-by:/)) {
 413                                 WARN("Signed-off-by: is the preferred form\n" .
 414                                         $herecurr);
 415                         }
 416                         if ($line =~ /^\s*signed-off-by:\S/i) {
 417                                 WARN("need space after Signed-off-by:\n" .
 418                                         $herecurr);
 419                         }
 420                 }
 421
 422 # Check for wrappage within a valid hunk of the file
 423                 if ($realcnt != 0 && $line !~ m{^(?:\+|-| |$)}) {
 424                         ERROR("patch seems to be corrupt (line wrapped?)\n" .
 425                                 $herecurr);
 426                 }
 427
 428 # UTF-8 regex found at http://www.w3.org/International/questions/qa-forms-utf-8.en.php
 429                 if (($realfile =~ /^$/ || $line =~ /^\+/) &&
 430                      !($line =~ m/^(
 431                                 [\x09\x0A\x0D\x20-\x7E]              # ASCII
 432                                 | [\xC2-\xDF][\x80-\xBF]             # non-overlong 2-byte
 433                                 |  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
 434                                 | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
 435                                 |  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
 436                                 |  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
 437                                 | [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
 438                                 |  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
 439                                 )*$/x )) {
 440                         ERROR("Invalid UTF-8\n" . $herecurr);
 441                 }
 442
 443 #ignore lines being removed
 444                 if ($line=~/^-/) {next;}
 445
 446 # check we are in a valid source file if not then ignore this hunk
 447                 next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);
 448
 449 #trailing whitespace
 450                 if ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
 451                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 452                         ERROR("trailing whitespace\n" . $herevet);
 453                 }
 454 #80 column limit
 455                 if ($line =~ /^\+/ && !($prevline=~/\/\*\*/) && $length > 80) {
 456                         WARN("line over 80 characters\n" . $herecurr);
 457                 }
 458
 459 # check we are in a valid source file *.[hc] if not then ignore this hunk
 460                 next if ($realfile !~ /\.[hc]$/);
 461
 462 # at the beginning of a line any tabs must come first and anything
 463 # more than 8 must use tabs.
 464                 if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
 465                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 466                         ERROR("use tabs not spaces\n" . $herevet);
 467                 }
 468
 469                 #
 470                 # The rest of our checks refer specifically to C style
 471                 # only apply those _outside_ comments.
 472                 #
 473                 next if ($in_comment);
 474
 475 # Remove comments from the line before processing.
 476                 $line =~ s@/\*.*\*/@@g;
 477                 $line =~ s@/\*.*@@;
 478                 $line =~ s@.*\*/@@;
 479
 480 # Standardise the strings and chars within the input to simplify matching.
 481                 $line = sanitise_line($line);
 482
 483 #
 484 # Checks which may be anchored in the context.
 485 #
 486
 487 # Check for switch () and associated case and default
 488 # statements should be at the same indent.
 489                 if ($line=~/\bswitch\s*\(.*\)/) {
 490                         my $err = '';
 491                         my $sep = '';
 492                         my @ctx = ctx_block_outer($linenr, $realcnt);
 493                         shift(@ctx);
 494                         for my $ctx (@ctx) {
 495                                 my ($clen, $cindent) = line_stats($ctx);
 496                                 if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
 497                                                         $indent != $cindent) {
 498                                         $err .= "$sep$ctx\n";
 499                                         $sep = '';
 500                                 } else {
 501                                         $sep = "[...]\n";
 502                                 }
 503                         }
 504                         if ($err ne '') {
 505                                 ERROR("switch and case should be at the same indent\n$hereline\n$err\n");
 506                         }
 507                 }
 508
 509 # if/while/etc brace do not go on next line, unless defining a do while loop,
 510 # or if that brace on the next line is for something else
 511                 if ($line =~ /\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.#/) {
 512                         my @ctx = ctx_statement($linenr, $realcnt);
 513                         my $ctx_ln = $linenr + $#ctx + 1;
 514                         my $ctx_cnt = $realcnt - $#ctx - 1;
 515                         my $ctx = join("\n", @ctx);
 516
 517                         while ($ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^-/) {
 518                                 $ctx_ln++;
 519                                 $ctx_cnt--;
 520                         }
 521                         ##warn "line<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>";
 522
 523                         if ($ctx !~ /{\s*/ && $ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
 524                                 ERROR("That { should be on the previous line\n" .
 525                                         "$here\n$ctx\n$lines[$ctx_ln - 1]");
 526                         }
 527                 }
 528
 529 #ignore lines not being added
 530                 if ($line=~/^[^\+]/) {next;}
 531
 532 # TEST: allow direct testing of the type matcher.
 533                 if ($tst_type && $line =~ /^.$Declare$/) {
 534                         ERROR("TEST: is type $Declare\n" . $herecurr);
 535                         next;
 536                 }
 537
 538 #
 539 # Checks which are anchored on the added line.
 540 #
 541
 542 # check for malformed paths in #include statements (uses RAW line)
 543                 if ($rawline =~ m{^.#\s*include\s+[<"](.*)[">]}) {
 544                         my $path = $1;
 545                         if ($path =~ m{//}) {
 546                                 ERROR("malformed #include filename\n" .
 547                                         $herecurr);
 548                         }
 549                         # Sanitise this special form of string.
 550                         $path = 'X' x length($path);
 551                         $line =~ s{\<.*\>}{<$path>};
 552                 }
 553
 554 # no C99 // comments
 555                 if ($line =~ m{//}) {
 556                         ERROR("do not use C99 // comments\n" . $herecurr);
 557                 }
 558                 # Remove C99 comments.
 559                 $line =~ s@//.*@@;
 560
 561 #EXPORT_SYMBOL should immediately follow its function closing }.
 562                 if (($line =~ /EXPORT_SYMBOL.*\((.*)\)/) ||
 563                     ($line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
 564                         my $name = $1;
 565                         if (($prevline !~ /^}/) &&
 566                            ($prevline !~ /^\+}/) &&
 567                            ($prevline !~ /^ }/) &&
 568                            ($prevline !~ /\s$name(?:\s+$Attribute)?\s*(?:;|=)/)) {
 569                                 WARN("EXPORT_SYMBOL(foo); should immediately follow its function/variable\n" . $herecurr);
 570                         }
 571                 }
 572
 573 # check for static initialisers.
 574                 if ($line=~/\s*static\s.*=\s+(0|NULL);/) {
 575                         ERROR("do not initialise statics to 0 or NULL\n" .
 576                                 $herecurr);
 577                 }
 578
 579 # check for new typedefs, only function parameters and sparse annotations
 580 # make sense.
 581                 if ($line =~ /\btypedef\s/ &&
 582                     $line !~ /\btypedef\s+$Type\s+\(\s*\*$Ident\s*\)\s*\(/ &&
 583                     $line !~ /\b__bitwise(?:__|)\b/) {
 584                         WARN("do not add new typedefs\n" . $herecurr);
 585                 }
 586
 587 # * goes on variable not on type
 588                 if ($line =~ m{\($NonptrType(\*+)(?:\s+const)?\)}) {
 589                         ERROR("\"(foo$1)\" should be \"(foo $1)\"\n" .
 590                                 $herecurr);
 591
 592                 } elsif ($line =~ m{\($NonptrType\s+(\*+)(?!\s+const)\s+\)}) {
 593                         ERROR("\"(foo $1 )\" should be \"(foo $1)\"\n" .
 594                                 $herecurr);
 595
 596                 } elsif ($line =~ m{$NonptrType(\*+)(?:\s+const)?\s+[A-Za-z\d_]+}) {
 597                         ERROR("\"foo$1 bar\" should be \"foo $1bar\"\n" .
 598                                 $herecurr);
 599
 600                 } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+const)\s+[A-Za-z\d_]+}) {
 601                         ERROR("\"foo $1 bar\" should be \"foo $1bar\"\n" .
 602                                 $herecurr);
 603                 }
 604
 605 # # no BUG() or BUG_ON()
 606 #               if ($line =~ /\b(BUG|BUG_ON)\b/) {
 607 #                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
 608 #                       print "$herecurr";
 609 #                       $clean = 0;
 610 #               }
 611
 612 # printk should use KERN_* levels.  Note that follow on printk's on the
 613 # same line do not need a level, so we use the current block context
 614 # to try and find and validate the current printk.  In summary the current
 615 # printk includes all preceeding printk's which have no newline on the end.
 616 # we assume the first bad printk is the one to report.
 617                 if ($line =~ /\bprintk\((?!KERN_)/) {
 618                         my $ok = 0;
 619                         for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
 620                                 #print "CHECK<$lines[$ln - 1]\n";
 621                                 # we have a preceeding printk if it ends
 622                                 # with "\n" ignore it, else it is to blame
 623                                 if ($lines[$ln - 1] =~ m{\bprintk\(}) {
 624                                         if ($rawlines[$ln - 1] !~ m{\\n"}) {
 625                                                 $ok = 1;
 626                                         }
 627                                         last;
 628                                 }
 629                         }
 630                         if ($ok == 0) {
 631                                 WARN("printk() should include KERN_ facility level\n" . $herecurr);
 632                         }
 633                 }
 634
 635 # function brace can't be on same line, except for #defines of do while,
 636 # or if closed on same line
 637                 if (($line=~/$Type\s*[A-Za-z\d_]+\(.*\).* {/) and
 638                     !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
 639                         ERROR("open brace '{' following function declarations go on the next line\n" . $herecurr);
 640                 }
 641
 642 # Check operator spacing.
 643                 # Note we expand the line with the leading + as the real
 644                 # line will be displayed with the leading + and the tabs
 645                 # will therefore also expand that way.
 646                 my $opline = $line;
 647                 $opline = expand_tabs($opline);
 648                 $opline =~ s/^./ /;
 649                 if (!($line=~/\#\s*include/)) {
 650                         my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
 651                         my $off = 0;
 652                         for (my $n = 0; $n < $#elements; $n += 2) {
 653                                 $off += length($elements[$n]);
 654
 655                                 my $a = '';
 656                                 $a = 'V' if ($elements[$n] ne '');
 657                                 $a = 'W' if ($elements[$n] =~ /\s$/);
 658                                 $a = 'B' if ($elements[$n] =~ /(\[|\()$/);
 659                                 $a = 'O' if ($elements[$n] eq '');
 660                                 $a = 'E' if ($elements[$n] eq '' && $n == 0);
 661
 662                                 my $op = $elements[$n + 1];
 663
 664                                 my $c = '';
 665                                 if (defined $elements[$n + 2]) {
 666                                         $c = 'V' if ($elements[$n + 2] ne '');
 667                                         $c = 'W' if ($elements[$n + 2] =~ /^\s/);
 668                                         $c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
 669                                         $c = 'O' if ($elements[$n + 2] eq '');
 670                                 } else {
 671                                         $c = 'E';
 672                                 }
 673
 674                                 # Pick up the preceeding and succeeding characters.
 675                                 my $ca = substr($opline, 0, $off);
 676                                 my $cc = '';
 677                                 if (length($opline) >= ($off + length($elements[$n + 1]))) {
 678                                         $cc = substr($opline, $off + length($elements[$n + 1]));
 679                                 }
 680                                 my $cb = "$ca$;$cc";
 681
 682                                 my $ctx = "${a}x${c}";
 683
 684                                 my $at = "(ctx:$ctx)";
 685
 686                                 my $ptr = (" " x $off) . "^";
 687                                 my $hereptr = "$hereline$ptr\n";
 688
 689                                 ##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
 690
 691                                 # ; should have either the end of line or a space or \ after it
 692                                 if ($op eq ';') {
 693                                         if ($ctx !~ /.x[WEB]/ && $cc !~ /^\\/ &&
 694                                             $cc !~ /^;/) {
 695                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
 696                                         }
 697
 698                                 # // is a comment
 699                                 } elsif ($op eq '//') {
 700
 701                                 # -> should have no spaces
 702                                 } elsif ($op eq '->') {
 703                                         if ($ctx =~ /Wx.|.xW/) {
 704                                                 ERROR("no spaces around that '$op' $at\n" . $hereptr);
 705                                         }
 706
 707                                 # , must have a space on the right.
 708                                 } elsif ($op eq ',') {
 709                                         if ($ctx !~ /.xW|.xE/ && $cc !~ /^}/) {
 710                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
 711                                         }
 712
 713                                 # unary ! and unary ~ are allowed no space on the right
 714                                 } elsif ($op eq '!' or $op eq '~') {
 715                                         if ($ctx !~ /[WOEB]x./) {
 716                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 717                                         }
 718                                         if ($ctx =~ /.xW/) {
 719                                                 ERROR("no space after that '$op' $at\n" . $hereptr);
 720                                         }
 721
 722                                 # unary ++ and unary -- are allowed no space on one side.
 723                                 } elsif ($op eq '++' or $op eq '--') {
 724                                         if ($ctx !~ /[WOB]x[^W]/ && $ctx !~ /[^W]x[WOBE]/) {
 725                                                 ERROR("need space one side of that '$op' $at\n" . $hereptr);
 726                                         }
 727                                         if ($ctx =~ /Wx./ && $cc =~ /^;/) {
 728                                                 ERROR("no space before that '$op' $at\n" . $hereptr);
 729                                         }
 730
 731                                 # & is both unary and binary
 732                                 # unary:
 733                                 #       a &b
 734                                 # binary (consistent spacing):
 735                                 #       a&b             OK
 736                                 #       a & b           OK
 737                                 #
 738                                 # boiling down to: if there is a space on the right then there
 739                                 # should be one on the left.
 740                                 #
 741                                 # - is the same
 742                                 #
 743                                 } elsif ($op eq '&' or $op eq '-') {
 744                                         if ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]/) {
 745                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 746                                         }
 747
 748                                 # * is the same as & only adding:
 749                                 # type:
 750                                 #       (foo *)
 751                                 #       (foo **)
 752                                 #
 753                                 } elsif ($op eq '*') {
 754                                         if ($ca !~ /$Type$/ && $cb !~ /(\*$;|$;\*)/ &&
 755                                             $ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]|OxV|WxB|BxB/) {
 756                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 757                                         }
 758
 759                                 # << and >> may either have or not have spaces both sides
 760                                 } elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
 761                                          $op eq '^' or $op eq '|')
 762                                 {
 763                                         if ($ctx !~ /VxV|WxW|VxE|WxE/) {
 764                                                 ERROR("need consistent spacing around '$op' $at\n" .
 765                                                         $hereptr);
 766                                         }
 767
 768                                 # All the others need spaces both sides.
 769                                 } elsif ($ctx !~ /[EW]x[WE]/) {
 770                                         ERROR("need spaces around that '$op' $at\n" . $hereptr);
 771                                 }
 772                                 $off += length($elements[$n + 1]);
 773                         }
 774                 }
 775
 776 #need space before brace following if, while, etc
 777                 if ($line =~ /\(.*\){/ || $line =~ /do{/) {
 778                         ERROR("need a space before the open brace '{'\n" . $herecurr);
 779                 }
 780
 781 # closing brace should have a space following it when it has anything
 782 # on the line
 783                 if ($line =~ /}(?!(?:,|;|\)))\S/) {
 784                         ERROR("need a space after that close brace '}'\n" . $herecurr);
 785                 }
 786
 787 #goto labels aren't indented, allow a single space however
 788                 if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
 789                    !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
 790                         WARN("labels should not be indented\n" . $herecurr);
 791                 }
 792
 793 # Need a space before open parenthesis after if, while etc
 794                 if ($line=~/\b(if|while|for|switch)\(/) {
 795                         ERROR("need a space before the open parenthesis '('\n" . $herecurr);
 796                 }
 797
 798 # Check for illegal assignment in if conditional.
 799                 if ($line=~/\bif\s*\(.*[^<>!=]=[^=].*\)/) {
 800                         #next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
 801                         ERROR("do not use assignment in if condition\n" . $herecurr);
 802                 }
 803
 804                 # Check for }<nl>else {, these must be at the same
 805                 # indent level to be relevant to each other.
 806                 if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
 807                                                 $previndent == $indent) {
 808                         ERROR("else should follow close brace '}'\n" . $hereprev);
 809                 }
 810
 811 #studly caps, commented out until figure out how to distinguish between use of existing and adding new
 812 #               if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
 813 #                   print "No studly caps, use _\n";
 814 #                   print "$herecurr";
 815 #                   $clean = 0;
 816 #               }
 817
 818 #no spaces allowed after \ in define
 819                 if ($line=~/\#define.*\\\s$/) {
 820                         WARN("Whitepspace after \\ makes next lines useless\n" . $herecurr);
 821                 }
 822
 823 #warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
 824                 if ($tree && $rawline =~ m{^.\#\s*include\s*\<asm\/(.*)\.h\>}) {
 825                         my $checkfile = "include/linux/$1.h";
 826                         if (-f $checkfile) {
 827                                 CHK("Use #include <linux/$1.h> instead of <asm/$1.h>\n" .
 828                                         $herecurr);
 829                         }
 830                 }
 831
 832 # if and else should not have general statements after it
 833                 if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/ &&
 834                     $1 !~ /^\s*(?:\sif|{|\\|$)/) {
 835                         ERROR("trailing statements should be on next line\n" . $herecurr);
 836                 }
 837
 838 # multi-statement macros should be enclosed in a do while loop, grab the
 839 # first statement and ensure its the whole macro if its not enclosed
 840 # in a known goot container
 841                 if (($prevline=~/\#define.*\\/) and
 842                    !($prevline=~/do\s+{/) and !($prevline=~/\(\{/) and
 843                    !($line=~/do.*{/) and !($line=~/\(\{/) and
 844                    !($line=~/^.\s*$Declare\s/)) {
 845                         # Grab the first statement, if that is the entire macro
 846                         # its ok.  This may start either on the #define line
 847                         # or the one below.
 848                         my $ln = $linenr;
 849                         my $cnt = $realcnt;
 850
 851                         # If the macro starts on the define line start there.
 852                         if ($prevline !~ m{^.#\s*define\s*$Ident(?:\([^\)]*\))?\s*\\\s*$}) {
 853                                 $ln--;
 854                                 $cnt++;
 855                         }
 856                         my @ctx = ctx_statement($ln, $cnt);
 857                         my $ctx_ln = $ln + $#ctx + 1;
 858                         my $ctx = join("\n", @ctx);
 859
 860                         # Pull in any empty extension lines.
 861                         while ($ctx =~ /\\$/ &&
 862                                $lines[$ctx_ln - 1] =~ /^.\s*(?:\\)?$/) {
 863                                 $ctx .= $lines[$ctx_ln - 1];
 864                                 $ctx_ln++;
 865                         }
 866
 867                         if ($ctx =~ /\\$/) {
 868                                 if ($ctx =~ /;/) {
 869                                         ERROR("Macros with multiple statements should be enclosed in a do - while loop\n" . "$here\n$ctx\n");
 870                                 } else {
 871                                         ERROR("Macros with complex values should be enclosed in parenthesis\n" . "$here\n$ctx\n");
 872                                 }
 873                         }
 874                 }
 875
 876 # don't include deprecated include files (uses RAW line)
 877                 for my $inc (@dep_includes) {
 878                         if ($rawline =~ m@\#\s*include\s*\<$inc>@) {
 879                                 ERROR("Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n" . $herecurr);
 880                         }
 881                 }
 882
 883 # don't use deprecated functions
 884                 for my $func (@dep_functions) {
 885                         if ($line =~ /\b$func\b/) {
 886                                 ERROR("Don't use $func(): see Documentation/feature-removal-schedule.txt\n" . $herecurr);
 887                         }
 888                 }
 889
 890 # no volatiles please
 891                 if ($line =~ /\bvolatile\b/ && $line !~ /\basm\s+volatile\b/) {
 892                         WARN("Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n" . $herecurr);
 893                 }
 894
 895 # warn about #if 0
 896                 if ($line =~ /^.#\s*if\s+0\b/) {
 897                         CHK("if this code is redundant consider removing it\n" .
 898                                 $herecurr);
 899                 }
 900
 901 # warn about #ifdefs in C files
 902 #               if ($line =~ /^.#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
 903 #                       print "#ifdef in C files should be avoided\n";
 904 #                       print "$herecurr";
 905 #                       $clean = 0;
 906 #               }
 907
 908 # check for spinlock_t definitions without a comment.
 909                 if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/) {
 910                         my $which = $1;
 911                         if (!ctx_has_comment($first_line, $linenr)) {
 912                                 CHK("$1 definition without comment\n" . $herecurr);
 913                         }
 914                 }
 915 # check for memory barriers without a comment.
 916                 if ($line =~ /\b(mb|rmb|wmb|read_barrier_depends|smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
 917                         if (!ctx_has_comment($first_line, $linenr)) {
 918                                 CHK("memory barrier without comment\n" . $herecurr);
 919                         }
 920                 }
 921 # check of hardware specific defines
 922                 if ($line =~ m@^.#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@) {
 923                         CHK("architecture specific defines should be avoided\n" .  $herecurr);
 924                 }
 925
 926 # check the location of the inline attribute, that it is between
 927 # storage class and type.
 928                 if ($line =~ /$Type\s+(?:inline|__always_inline)\b/ ||
 929                     $line =~ /\b(?:inline|always_inline)\s+$Storage/) {
 930                         ERROR("inline keyword should sit between storage class and type\n" . $herecurr);
 931                 }
 932
 933 # check for new externs in .c files.
 934                 if ($line =~ /^.\s*extern\s/ && ($realfile =~ /\.c$/)) {
 935                         WARN("externs should be avoided in .c files\n" .  $herecurr);
 936                 }
 937
 938 # checks for new __setup's
 939                 if ($rawline =~ /\b__setup\("([^"]*)"/) {
 940                         my $name = $1;
 941
 942                         if (!grep(/$name/, @setup_docs)) {
 943                                 CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
 944                         }
 945                 }
 946         }
 947
 948         if ($chk_patch && !$is_patch) {
 949                 ERROR("Does not appear to be a unified-diff format patch\n");
 950         }
 951         if ($is_patch && $chk_signoff && $signoff == 0) {
 952                 ERROR("Missing Signed-off-by: line(s)\n");
 953         }
 954
 955         if ($clean == 1 && $quiet == 0) {
 956                 print "Your patch has no obvious style problems and is ready for submission.\n"
 957         }
 958         if ($clean == 0 && $quiet == 0) {
 959                 print "Your patch has style problems, please review.  If any of these errors\n";
 960                 print "are false positives report them to the maintainer, see\n";
 961                 print "CHECKPATCH in MAINTAINERS.\n";
 962         }
 963         return $clean;
 964 }